I need to replace a broken tuning key on my 1980 (I think) Carvin bass. It is a Schaller enclosed tuner which requires a 15/32" hole - NOT the more common 9/16" that Schaller, Carvin and others make now. I haven't made any direct calls yet, but have looked at the online catalogs of Stewmac, Allparts, Carvin and others. No 15/32" keys are listed. Any suggestions on where to search? Bob