A whole [parasitic bomb] load of Mega Man prototypes are up for sale at the Hidden Palace:
Everything is going for well over a $100. You can either buy the proto itself or have them dump it for you. Either way, it's gonna cost.
I called Protodude for this. The seller is DreamTR, a prototype collector who is kindly willing to dump his prototypes in return for a bit of cash in return for what he originally invested in them. His "affiliate" who's posting this is "drx", who is also famous in the Sonic community for leaking over a thousand protos on Feb. 28, 2008.
Just thinking though, it probably wouldn't cost as much a say a copy of BioHazard/Resident Evil 1.5 for $2000. A prototype of Rockman X3 would most likely cost in the lower hundreds. But that's just me. I think we as a MM community should pitch in, make some sort of a donation drive, and buy as much as we can.
Again, that my rear end talking. No seriously, I think we all should take this opportunity before its gone for good.