Sorry to hear about your loss. Your challenge is interesting.

If you are comfortable with rack systems, and if you have a cool environment, and if you have enough current on your circuits, and if you can get these things booting from network/USB then you might want to check out http://www.theserverstore.com/content/dell-poweredge-c6105-servers - a off lease/refurb "DELL POWEREDGE C6105 8x OPTERON 4332HE 3GHZ SIX CORE CPU'S 64GB MEM " 48 cores under $US1K. Have bought off lease servers from them before, always good service. Be aware that it will draw a lot of current and be nosiy. If you can get it working without local hard disks it will save you $, heat and electricity.