Our arcade at a mall near us has two Rage in the Cages. Every year they put a price tag on them (and everything else) at some point. I'll keep a lookout and if it goes up for sale there, I'll get a hold of you.
Also, this is a long shot, but does anyone remember a basketball game from the early 90s... I want to say it was all black and had lights that went around the backboard or something and had a very carnival-y music that played with it? I can still remember the tune but I cant for the life of me remember the game.