OBERHEIM SYNTH

I'd suggest consulting Sound Doctorin'  
(http://sounddoctorin.com/synthtec/parts/key.htm).  It is the largest 
replacement key list I have found.
If you have your broken key, you can compare it to the pictures available and 
determine if an alternate key (Matrix-6? OB-8? Pratt & Read?) would fit.

Please share your findings when you find one.  My keyboard is fine, fortunately, 
but you never know. 


(I'll save this for a separate thread:  I was toying with the idea of painting 
keys to have a reverse color keyboard...)