Do you like tone of the Sunn?
If so getting it fixed is still cheaper ($140) than buying a new amp or pretty much any used amp.
OTOH, those particular Sunns are not astonishingly great sounding like some of the earlier solidstate ones. (Beta Bass?)
If I were you I'd pick up a used GK 400RB or Beta Bass. Then in the future get the Sunn fixed when it is convenient.
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