I just wanted to let everyone know that what died was indeed my output transformer (T8 on the schematic). These are the most common part to fail in the SX-28s...almost all of them died.
I contacted Peter W. Dahl -
http://www.pwdahl.com/ . He made me a beautiful hand-made replacement for about a hundred bucks, and this one should last a lot longer than the factory one. He paints them all in black, and it does have all 3 taps for different speakers. I highly recommend him to anyone needing a custom-wound transformer; he makes many different kinds.