Oh! I just remembered that a wrecking yard up here has an 87 300dl. I went up there to check it out and the motor is gone but maybe the metal piece from the shock is still on there.
If they don't have it, ask them to check their parts interchange system and they can tell you all the other models that have the same engine shock.
Then you can get the rubbers and everything from Discount Import (or elsewhere).

The wrecking yard is called All American Classics and it's in Vancouver, WA