If I thought there were a chance in heck I could desolder the surface-mount keyboard controller IC from the bad board and put it on my bad IIgs' I'd PM about it, but I'm only moderately competent with through-hole rework, I'm sure attempting to swap the keyboard IC would totally end in tears.
(This is why I love my "new" Apple II+; it's all generic ICs, and a lot of them are even already in sockets.)