Suggest an amplifier for my power supply

[steveu]

I would look at something like the LJM L10 modules available from various sources. You want at least two pair of output transistors per channels if not 3 or 4. The L10 uses 3 pair of 2SC5200+2SA1943 which should be able to handle +/-50V rails. You will just blow up a single pair. You can buy two channels and a protection + power supply from some sources.
Amazon.com: 2pcs 300W+300W Class AB 4R Amplifier AMP board: Musical Instruments

Also look at the L15 MOSFET amp.