Yamaha PSR-500 parts

Hi all.

I was recently able to get my hands on a Yamaha PSR-500m for a very good price ($15) and was trying to find out what other keyboards Yamaha makes that have interchangable parts (keys, rubber mats under the keys, etc.) Electronically the keyboard functions perfectly, but the cosmetic condition is a little grungey. I'm assuming the PSR-500 has parts that are swappable, but I just wanted to be certain and find out if any other keyboards Yamaha has made contain parts that I can swap in and out.

That keyboard is pretty old, and i really doubt you can find original spare parts for it.

I guess you can order parts for the keyboards that are being sold now, and the ones
that got discontinued recently in your local yamaha dealer.