You'll need to check the system maps to find stations at which they are not Prohibited, if you want to sell them at the commodities market. I believe Erevate is Federation space, so they're gonna be considered illegal goods at almost any Federation station. You can also sell them at a black market, if you do manage to make your way into a station that forbids them and also has a black market, but unless you bought them for much lower than normal you aren't necessarily going to make a profit that way.
Your best buyers will probably also be warzone areas with a lot of conflict, though I haven't done much trading so I'm not sure of the easiest way to identify who those are.
If you didn't buy them and just found some floating out in space, they'll be considered Stolen (the concept of salvage is unfortunately not implemented in the game yet) and your only option is to go to a black market station.
