So Rothbard is okay with taking government money?

My position is that by using accounting methods we can start to provide proof of ownership for things stolen by the state. This opposes the notion that once the state steals, title is erased.

That’s a value judgment. I’m not making those. I also have no idea what “acceptable” means in the context of the question.

If someone is for non-aggression, and they don’t regard the state as aggressive, then I think that is a failure to understand non-aggression.

If someone walks on a sidewalk, I’m not sure that is an explicit endorsement of the state. The state creates obstacles for us, I don’t see traversing those obstacles to pursue things we would otherwise be able to do in a free market as “using the state”.