[TenTec] 252Mo supply

[Bill ACITO, W1PA]

With my 540, I got a 262G that has two TO-3 pass 
transistors...   they are marked:

   S S S
PR216M

(actually, based on mounting holes on the heatsink, it looks 
like there was originally one, and then it was modified to 
two)

Any idea what the 2Nxxxx replacements are, or should be if I 
need to replace them?
Google was no help.  I love the multi-power-resistor ammeter 
shunt wrapped around the heatsink, btw.

Bill W1PA