Puddin' Man wrote:
....
What I've got is a little 20-yr-old Technics stereo receiver [that] ...appears to be ...dying......
What might I be able to do in terms of replacing the stereo receiver
....

Besides the other suggestions, look for local audio shop. Most any
larger locality will have one and likely will either do repair or can
direct you to person(s) who can. Depending on the model, they may or
may not want to mess with it, but it's worth looking into. Had my old
Kenwood that is nearly 30 now (next year, if memory serves) totally
refurbed two years ago -- new lights, new output power transistors (one
of them died was final causation), replaced a bunch of caps that were
weak or suspect, cleaned it all out, etc., etc., ... It should go on
for another significant lifetime.