Richard:
Absolutely NOT A PROBLEM replacing your old amp with a new one and
using the existing speakers. The slight difference in "Watts / rating"
of the amp and the speakers is not going to matter at all.
..... on the other hand, why don't you get your "old" amp fixed? Maybe
just a minor problem. At the very least TAKE it to a service shop for
a repair cost estimate so you can make an intelligent repair decision
with facts instead of guesses. It might be cheaper to fix it than to
buy a new one.
electricitym
..
..