I don’t think in nationalist framing. Nation-states promote tribalism. Materialism and Marxism is a way of thinking of social relations. As an economy of trade, I’m gonna go with the Incan Empire as a great example of socialism:

Each citizen of the empire was issued the necessities of life out of the state storehouses, including food, tools, raw materials, and clothing, and needed to purchase nothing. With no shops or markets, there was no need for a standard currency or money, and there was nowhere to spend money or purchase or trade for necessities.

Thanks for the thoughtful question. For a present example, I would probably go with a social democracy like Norway. It is impossible globally to not be affected by capitalism. And I would rather live in an economy with strong social networks than live under the siege mentality of Vietnam, although China seems to be trying to find a balance.