I'm not near the map at the moment but you will often find black markets at independent stations in faction owned systems. Some have said BM's are difficult to find in Imperial space but I haven't struggled since working this out.
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Just checked: Try Zebrowski Prospect @ Frendian
I believe Santos is in the same system and may have a market also and is <100ls. I'm relying on badly scribbled notes and Zebrowski was the only certainty
I'm going to have to put my other hat on and go bounty hunting in Yembo soon. Was pirating it yesterday, and didn't see any other pirates. Might have to wait a little more for people to get those unpaid fines adding up.