uber actually happens to be rather correct. certain internal G5 components are hardwired into the enclosure.In some cases, apple replaces the entire enclosure. If you were to try and buy one stock, you'd pay over 5-600 for them. (actual cost) Luckily, we service providers arent required to send the damaged/defective cases back. So, we end up with them from time to time. Contacting an apple authorized service provider or specialist might yield you a case but I wouldnt get my hopes super high. We dont see them that often. Since the G5 shipped, I've seen three. Ironically, two of which are in the proces of becoming my G5 coffee table.

But, if you really want one, it never hurts to call around smile
Electricity tastes good. No, seriously.