Where is a good place to find a mac plus mouse?

eBay has no such items.

Are other mice compatible? (ie. from other Macs / Amigas etc? Obviously not serial, ps2, ADB).

Update: Found this http://www.megadon.co.uk/wb/whiteboardshow.pl/syrinx/wbfile=Mac%20Plus%20Mouse.wb/page=default.html

Not overly confident with electronics, so will continue looking.