Thanks for the pinout - that didn't come up in my google search. I have the SM now and it shows the pinouts. I don't know what the gain is - the information in my previous post is the most i have been able to find. I will try the KSC945s - I have a couple but will need to pick up some more - there are 12 of them on this board and there aren't any other transistors here - just the capacitors and a couple of resistors which almost never go south. Aside from the 537s, I can't imagine what else would be happening on this board. Will probably replace the handful of caps here as well while I have access to it. Thankfully it isn't hard to get to.