Rebuild or New?

I’ve been thinking it’s time for a new amp. I have a Carver 200t Magnetic I bought new in 1987. I’ve run the hell out of it. No joke, there has got to be thousands of hours on this thing. It’s never failed me at all. I wonder though, after years of use, could degradation with the electronic parts have slowly, imperceptibly, colored the sound?

A friend told me two things are the enemy of electronics, vibration and heat. So, I have to wonder.

Am not sure but can these things be rebuilt with newer components? Or, should I just get a new amp?