I have a B77, I also have a PR99 manual. Checking them both it sure looks the same to me. The PR99 uses the same type heads as an A77, B77 going by my manual.
The cover is in two parts of course, inner and outer.
Sorry guys, didn't explain myself too well. I am talking about the plate which covers all the heads and the capstan which clips into place over the top of the heads and has the word "REVOX" on it. I could make one but it will look a bit ....
Steve