XP-60 FDD can be easily replaced. Just get a genuine sony black drive and if I remember correctly there was some jumper to be changed on the drive (or maybe not). There were sompatibility troubles with samsung and teac (or maybe not) drives if I recall correctly, as there was some line used that is not used in comp.
Search around net on the topics of replacing FDDs in synths of 90-ties. I have changed drives for a few XP-80 and other board of the time, worked fine.
Remember some weird drives that were used in some yamahas and kurzweils (or maybe not), that had a belt drive (!) and unusual/nonstandard connectors and onboard logic.