The auction was ended with a "buy it now". No problem then if it doesn't bode well for emulation, it can be simulated until it's emulated one day.
The only Mego STPB on Ebay right now is this one:
It's at $172 US and still going. At $50 it was a bargain, but who knows...there may be one that will pop-up for dirt cheap. It's only a question of when and how much.