J M Fahey and Brymus:
Thanks for your comments and suggestions. I'll definitely be looking at Apex for a transformer. The toroids look promising and it should be fairly easy to mount one in the amp. I'll start trying to sort out the reason for the transformer failure and any tips about that search would be welcome.
I believe the finals are 2SD-613E's which cross to an ECG377. I don't know how this would compare to a TIP31 set. Oh, and I've just recently learned of the chipamps and will look to building one soon.
Again, thanks to both of you and best regards,
Strick