In playing around with quite a few older Rf's when I was finding my personal system, I stumbled on an easy and inexpensive seal replacement system.
Black foam closed cell sheets can be had in the craft section of big discount stores for less than a buck each...each sheet will do probably 10-20 cameras. In the same section, you'll be able to find acid-free spray craft adhesive (one can is, again, more than you'll need).
Spray the back of the foam sheet with adhesive, then cover the application with waxed paper. Now, ONE SECTION AT A TIME, clean the goo out of the back of your camera, scraping with wood toothpicks and swabbing with alcohol. Cut a replacement for each strip down the channels, and pad(s) for the door ends. Peel the waxed apaper off and apply to the now cleaned area. Cake!