I bought a set of these a couple months ago for $50 & $25 shipping.
The bass and satelite speaker enclosures have a couple small scratches / dings, nothing structural or that can be seen from more than 3 feet away. I'm building a jukebox and installing these and I bought a set of Pioneer 260w 6 1/2 car speakers that I'll be installing with them. I'm currently running all 4 speakers and they sound GREAT! in fact I'm listening to them right now.
Yes, the volume / bass control can be removed from the satelite speaker and even de-cased easily if you want to drill 2 holes and install it in your cab. The speaker wires attach to the bass / amp with one of those (I don't know the technical term), but you push on it and insert the bare speaker wire, not special plugs or jacks. Couldn't be simpler to extend, just buy some more speaker wire and twist them together. I'd solder them too, if you can, or wire nuts or good electrical tape wrapping.
I wish I'd used these for my MAME cab, too! You will like them A LOT!