You mean six string guitars, not basses, right? I used to own a Bich back in the late 80s. It was a custom job (but not for me) in quilted maple with the cloud inlays on the fretboard and maxed out electronics. The neck was factory ordered ultra-thin and I couldn't get it to hold a setup here in New England, so I traded it away.
Those things appear around here from time to time, so I'll keep my eyes open. Koa was pretty popular back in those days, too, so you could get lucky.
-bob