Master Vac Assembly

[sobeman]

Mine is leaking out the back side down the brake booster housing and needs to be replaced and I was going to replace the Master assembly as well but am having a hell of a time finding replacement parts for these. Searching the interwebs for the below part#'s come back with all kinds of stuff and the one that are exact part number cost over $1,000.00. Any help sourcing replacements would be highly appreciated. 

 

Car 1991 R32 Gtr 

Part# found on Master Vac assembly JKC 05U01 Part# found on Nengun 47210-05U01

Part# found on Master brake Cylinder 05U00 Part# found on Nengun 46010-05U00

[KiwiRS4T]

Are you leaking brake fluid? Pull the MC apart and inspect the bore. If its not badly pitted you can clean it up and put a new seal kit in it. A MC should be around $3-400

[sobeman]

I am certain the MC is leaking, I actually found one on ebay after posting this and ordered it. My question now is if brake fluid was leaking on the back side (firewall side) of the brake booster is the internals of the brake booster going to erode from the brake fluid?