Like Ryan said, if it's the mount at the rear of the transmission, I got mine at Rock Auto. Part numbers below are for OEM parts for my '95 SR.

There are supposed to be four "roll-stopper" cushions, kind of like washers, that sandwich in the two bolts. Not sure if those would need replacing as well, as I haven't installed my new one yet. I don't think they do, but their part number is MB932076.

The mount itself is part number MB951304 and it includes the two cushioned mounts in a small section that bolts up to the crossmember and then the transmission bolts to it. If that makes sense.

John B.