I sold one a month or 2 ago around $50-60 which was too low, but the buyer was international so it was $100 to him.
Personally, I think that it should be worth $75-80 because (well) used ones often sell $40-50 range. Those are nice white Alps boards, and the keys are nice, too.
PS - I have a cover if the buyer needs it. $18 shipped domestic.