Older MH repair parts - hard to find? Pls advise!

Yes, body parts can be a problem, although almost anything can be fabricated by a talented body shop. There are also a number of RV salvage yards where parts are available for many years and models. As far as appliances, etc. go, most of the same brands and even some models, are generally still used today, so that's usually not an issue. Even if an exact replacement is not available, a current unit can nearly always be fitted with minimal modifications.