This is not mine, but I just spotted it and thought I'd pass it on. An HP 715/64 w/ 256K L1. It's at $9.99 and has 1 bid, 4 hours to go.
It runs NS3.3 fine.
http://www.ebay.com/itm/Hp-PA-Risc-Powered-A4090A-Computer-Workstation-715-64-/291162319460?pt=US_Vintage_Computers_Mainframes&hash=item43caa06a64bp