DO you have any reason to think those caps are ACTUALLY bad? In my experience, those almost NEVER fail. (having said that, it now becomes almost a certainty they will...)
2N3055 is in fact one of the Peavey listed replacements for the SJ6392. The more modern replacement would be the MJ15015.
REplace the 5w resistors with the proper 5w types - 0.33 ohm.
Be aware that some of the 1N4148 diodes have parallel resitors that might confuse your tests.
2N3904 is one of the most common small transistors there is. I don't know why you'd need to sub it. An MPS8098 would be a nice pair to use if you must.
Q4,Q5 - look at the schematic. They are listed as 6530 and 6533 respectively. (MPS6530, MPS6533) These are limiter transistors in the circuit, most anything would work. MPS6531 and 6534 could also be used.