The zener diodes seem fairly easy to replace. ?A quick search on Mouser's web site comes up with the following as suitable replacements:
CR6 = MTZJ39SB R0G, a 36.3V 500mW Zener 2% ?$0.22 each
CR8 = TZX6V2C-TR, a 6.2V 500mW 2% ?$0.19 each
The power transistor isn't a 2N3106. ?From what I can find, the 2N3106 is a large stud cased SCR. ?What's the HP part number for the transistor?
Cheers,
Dave M
