Well I had located a rebuilt pump and was all set to order it and install it myself. I decided to take it by my local benz mechanic and just ask if there were alternatives such as removing the pump altogether. He did not recommend removing the pump but said he could replace the pully and bearings. I asked him specifically and he said MB does sell this separately. Apparently it is quite a BEAR to remove from the pump assembly though. So I got the new bearings and pully for about one-third the cost of a rebuilt pump.