I think you could ask the same.
Use a fixed price, and use amiga.org and or amibay.com, unless you want the insurance ebay gives.
Don't sell the keyboard. One day it will come to use. Either with a catweasel mk4, or another way. Only reason to sell it would be to help out a fellow amiga owner in need. So keep that unless someone desperate asks for it whom you take pity on.
Who knows? Sooner or later there is a os4, morph2 or aros capable platform that has catweasel capabilities, and then you want your keyboard:)
Or perhaps it's possible to write drivers for it using i minidin to usb adapter?
Keep it:)