Original Pierburg PE20027 brake vacuum pump.
Excellent+ condition which has not been opened up as you can see from the yellow paint seal on the screw.
When I turn the spindle it has good resistance of the internal diaphragm.
I would say it doesn’t need to be rebuilt but if it does, it is priced accordingly considering there is a rebuilt one on the market for $499.

Sold as is but I also may have a rebuild kit for it.