First of all I'm pretty sure Marx these days is getting too much credit for the term and theory. Yes he spent a lot of time in the library, and yes he made a lot of charts and bullshit about capitalism, but the fact is he was part of a milieu where lots of people, many of them anarchists, many of them older than him, were talking about the same thing. Marx has so many disciples now, and so many of them are professors, he gets treated as if he came up with it, but Proudhon, Fourier and others had already theorized it before him. Proudhon for example wrote What Is Property? in 1840.
On a different note, I think Against His-story, Against Leviathan qualifies as not derivative of Marx. Of course Perlman is well aware of Marx, and wrote the best paraphrase of Marx that I'm aware of ("Reproduction of Daily Life"), but he takes leave in AHAL in the sense that he doesn't centralize capitalism but Leviathan.
One of the reasons Perlman is able to do this is that he's asking a different question than "what are the origins of capitalism". He's trying to understand colonization (AHAL starts as a footnote to The Strait, which is about the history of the place he lives when he's writing it), and he fully commits to it. You see some marxists trying to talk about colonization and patriarchy through the language of marxism, so they'll talk about it in the language of primitive accumulation. The problem is that in trying to challenge the limits of marxist discourse (dismissive of colonization, race, gender, etc) they end up accepting the framework and that relegates race, gender, etc as secondary. It's like a weird biblical debate where you're actually just trying to express your own ideas, but you have to find a scriptural reference for them in The Holy Book of Marx. Because you want the boring as fuck marxists to listen to you, or because your career opportunities, or something. Fuck it.
Anyway, I'd recommend checking out the Libertarian Labyrinth, I think it might give you a different angle on your question. Especially the anarchists who were around before or contemporary with Marx.