I finally got a replacement for my ol' Yorkville Beta 800 power amp that gave up the ghost a couple years ago: an Ashly FTX-1501 Series II. It's got MOSFET output transistors, and goes stereo to 185w@8ohm/275w@4ohm per channel or bridged mono for 550 watts, and sounds beautiful! Paid 180 used/excellent cond.
So now I've got modded 1968 Showman Reverb preamp> Ashly power amp (1 side of stereo)> 1x JBL E120.
Just thought I would share!