Someone here in the parts for sale section sells on oe appearing one w a black case and electronic internals for $25 to your door and I understand the some regs can handle more current??and not needed in your app here but I understand you can replace the grounded brush on one of the 69 earlier alts w a insulated brush holder from a 70 up alt to make an isolated field (later type) alt if you ever wanted to use an an earlier alt w a later type 70 up flat VR.