I removed the vacuum pump and it was beyond rebuilding. The brand name was Gast and I found an exact replacement from WWW.gopro.pro this site offers a lot of different vacuum pumps and compressors.
In fact Gast has improved several things on the pump.
There is a strong retaining flange. The pump is a little longer but slimmer. It now has a five blade fan. Better placement of the wiring and a different end cap.
I'll send Bill-NY photos to insert here.

Jim
I replaced my pump several years ago with a Gast series MOA the website for Gast was www.gastmfg.com
I have been looking for the paperwork for when I bought it but I can't find it and I don't remember any of the details such as who I bought it from or the cost. I guess the memory is the first thing to go.

Tim,

Mine is a Gast MOV-V111-JH Diaphragm and the cost was $279 with free shipping from www.GoPro.pro

Hope that helps jog your memory

Jim & Barb Pics...