OT: SCSI ribbon cable & adapters?

[jmw]

I'd like to  replace the floppy inside my peavey SP sampler and install an
internal ZIP.

I need a DB25 female ribbon cable to 50 pin internal SCSI connector. (I know
it must have a proper name but I can't seem to remember it now). 

Does anyone know of a source for such cables? I know that there must be
adapters out there
but 'net searches haven't yielded much success.

Thanks in advance.

john