In the first round, disconnect the output stage from the power supply and check the supply voltages.
If necessary, replace the electrolytic capacitors.
Based on the drawing, the type of the output transistors is 2SC3264, they can be replaced with a transistor with similar parameters, if the different encapsulation and the slightly smaller dissipation and collector current are not a problem. 2SC1943, 2SC2921 and similar.
Hello Stew!
You can find the circuit diagram of the amplifier here on the page.
https://elektrotanya.com/swr_california_blonde_sch.pdf/download.html
In the first round, disconnect the output stage from the power supply and check the supply voltages.
If necessary, replace the electrolytic capacitors.
Based on the drawing, the type of the output transistors is 2SC3264, they can be replaced with a transistor with similar parameters, if the different encapsulation and the slightly smaller dissipation and collector current are not a problem. 2SC1943, 2SC2921 and similar.
Good luck with the repair.
Best regards: Tony