[S]hould propose to them the resolutions of the Achorians...who long ago engaged in war in order to add to the dominions of their prince another kingdom, to which he had some pretensions by an ancient alliance: this they conquered, but found that the trouble of keeping it was equal to that by which it was gained; that the conquered people were always either in rebellion or exposed to foreign invasions, while they were obliged to be incessantly at war, either for or against them, and consequently could never disband their army; that in the meantime they were oppressed with taxes, their money went out of the kingdom, their blood was spilt for the glory of their king without procuring the least advantage to the people, who received not the smallest benefit from it even in time of peace; and that, their manners being corrupted by a long war, robbery and murders everywhere abounded, and their laws fell into contempt; while their king, distracted with the care of two kingdoms, was the less able to apply his mind to the interest of either. When they saw this, and that there would be no end to these evils, they by joint counsels made an humble address to their king, desiring him to choose which of the two kingdoms he had the greatest mind to keep, since he could not hold both; for they were too great a people to be governed by a divided king, since no man would willingly have a groom that should be in common between him and another. Upon which the good prince was forced to quit his new kingdom to one of his friends (who was not long after dethroned), and to be contented with his old one...therefore it seemed much more eligible that the king should improve his ancient kingdom all he could, and make it flourish as much as possible; that he should love his people, and be beloved of them; that he should live among them, govern them gently and let other kingdoms alone, since that which had fallen to his share was big enough, if not too big, for him.
To these things I would add that law among the Macarians...by which their king, on the day on which he began to reign, is tied by an oath, confirmed by solemn sacrifices, never to have at once above a thousand pounds of gold in his treasures, or so much silver as is equal to that in value. This law, they tell us, was made by an excellent king who had more regard to the riches of his country than to his own wealth, and therefore provided against the heaping up of so much treasure as might impoverish the people. He thought that moderate sum might be sufficient for any accident, if either the king had occasion for it against the rebels, or the kingdom against the invasion of an enemy; but that it was not enough to encourage a prince to invade other men’s rights—a circumstance that was the chief cause of his making that law. He also thought that it was a good provision for that free circulation of money so necessary for the course of commerce and exchange. And when a king must distribute all those extraordinary accessions that increase treasure beyond the due pitch, it makes him less disposed to oppress his subjects. Such a king as this will be the terror of ill men, and will be beloved by all the good.--Thomas More, Utopia.
In addition to Utopia, three other states are discussed in positive terms by Raphael Hythloday in the narrative of Thomas More's Utopia. In addition to Achoria and Macaria (see above), which are both said to be near to Utopia, Hythloday also treats the penal laws of the otherwise unknown Polylerits (who live near Persia) in favorable fashion. The praise is a bit surprising because in all three states there is property; yet Hythloday also says that I must freely own that as long as there is any property, and while money is the standard of all other things, I cannot think that a nation can be governed either justly or happily: not justly, because the best things will fall to the share of the worst men; nor happily, because all things will be divided among a few (and even these are not in all respects happy), the rest being left to be absolutely miserable. In all three states there is property. Even so the Polylyrits are said to be "well-governed people" and "contented;" the post-revolt constitution of the Achorians, makes it "possible" that Achoria can "flourish;" and the public spirited ancient Macarian king has created laws that allow kings to be "beloved."
So, while from the vantage point of Utopian blueprint, Achoria, Macaria, and Polylerita (?) are not perfect, they are decidely better than the great European kingdoms (France, England, etc.) treated rather critically in Utopia. So, let's assume they are second-best in the Platonic sense. Achoria and Macaria are kingdoms while Polylerita is a republic (although Achoria has become a parliamentary monarchy of some sorts). What they do have in common is that they are all three not war-like. They are pacific in the sense that they do not aim to conquer or dominate others--at least two of the three states are (like Plato's city of pigs) organized for defensive war. They achieve their (relative) pacifism in three different ways: Polylerita is a protectorate (or vassal state) of Persia (to whom is pays tribute); Macaria has an institutional mechanism by which the state is simply too poor to fight wars abroad; and in Achoria the people seem to control the purse strings such that they can discourage the King from fighting abroad. This pacifism anticipates the Utopians's stance although in many respects these three states are less imperial and dominating than Utopia (which has non-trivial power over its neighbors). If avoiding war is More's most fundamental concern in Utopia -- and there is some evidence that this could be true --, then these three states are, in fact, better exemplars than Utopia. Of course, there are good reasons to see the institutions of property and war as linked, especially in a (late Feudal) state-building context of the fifteenth and sixteenth centuries
It is implied that in Macaria and Achoria the proposed war-avoiding mechanisms are stable (the laws have been around for quite some time). But this is not obvious; in Macaria it's not just the origin of the institution, which relies on great self-command and public spiritedness of the king that changed the constitution; its persistence also relies on self-limitation by existing kings. The Achorian settlement relies on ongoing vigilance of the people; whatever the ongoing merits of their argument(s) against imperial conquest, it's not obvious that future kings will always only act on their interest. Moreover, as historical example suggests, the people may also approve of conquest abroad (classical Athens's expedition against Sicily comes to mind as well as a few more recent ones). Finally, the fate of Polylerita is -- like all protectorates -- tied to the fate of its overlord, the Persian kingdom; if the Persian kings are conquered or if its internal politics change, Polylerita may be forced to be embroiled in future wars of conquest. That Raphael Hythloday does not note these fairly obvious limitations (nor his own inconsistency) suggests that for all the Socratic echoes in his words he may be less wise than he assumes.
It does not follow that no society can be pacific without abolishing property (and not being a vasal), but about that some other time more.