This series of videos demonstrates the Vako Orchestron sample playback keyboard, which was an improved version of the Mattel Optigan optical disc playback sampler.
via Optigan.com, which is making new sound discs for both the Optigan and Orchestron.
I can't imagine it would be too hard to make one of these keyboards with a switch that re-assigns the keys, to be compatible with both kinds of discs.