www.logickeyboard.com takes real Apple keyboards and puts new key caps on them for Final Cut. You can also take your existing keyboard and retrofit it with their key caps (everything they sell for G5 Macs will work on an Intel Mac).
There appears to be a vendor, Bella, that also makes a Final Cut keyboard which is much cheaper.
Just google "final cut keyboard" and you'll find several, most of which are just retrofitted Apple keyboards.
tooki