I too would like to know how much a rear main seal replacement costs. I have the exact same oil-leak symptoms on my '84 300D. It leaks about 1/2 ounce every time I park for any length of time, and it seems to come from the bell housing area. I had a main seal replaced on a Volvo 240, and it cost me $400. I would be surprised if that amount would be sufficient for the same job on a Mercedes...
1995 E300 Diesel (Die Blau Frau)