You should also read Vincent Geloso and Peter T. Lesson’s article “Are Anarcho-Capitalists Insane? Living Standards under Medieval Icelandic Conflict Institutions”. They empirically revisit the 1979 seminal paper of David Friedman in the Journal of Legal Studies regarding the law and economics of Iceland between 900 and 1262. The case is important because Iceland constitutes the first example in the literature on the economics of anarchy of how governance is a good that can privately be produced and with competition between providers. For nearly three centuries, Iceland was without a formal state (with a monopoly on violence) even though it was home to nearly one hundred thousands individuals. However, sustained private provision does not mean that the outcomes are superior than under formal governance.
There is also a podcast episode on this issue. Geloso explores anarcho-capitalist economic concepts and whether there are real life examples to back them up. It is a strong revisit to the most classical example in the literature.