Hi,
It is possible to find those Mistumi type CD-ROMS on ebay - I was looking before at the idea of changing the CD drive in a CDTV (which I believe is undoable). Aren't they the ones used with that custom interface - KDH or whatever its called - that was used on early Soundblaster cards?
I think Downix pointed me to a couple on US ebay, perhaps you could keep you eyes open?
Regards