can anyone help me with this i posted the below at Benzworld but so far nothing to help me out.

The 93 300D that I just bought with 148k seems like its due for the vacuum pump change. Its got the newer front cover on it with the screw but has the mercedes star on it so must be original. In looking on the net I see Pierburg and Hella and appears they are the same company. Is that correct, are they of the same quality. I found a Hella shipped for $280 at autopartswarehouse. Parts.com was $5 less but was unable to tell me who made the part other than its OEM. But could not say if its Pierburg.

Also it appears to be a fairly simple parts swap. I dont have a manual though and have been unable to find a how to thread. I assume there is not one as there's not much to it other than not over torquing the bolts.