All I have left are FAG units. If you want ATE specifically let me know and I can look for one.
New seal kits will need to be installed as these have been sitting for many decades.
Along with the other mufflers I have This part has been sitting in a warehouse since around the late 1980's. It's heavy at 17 lbs.
Left side is 071 256 091 B
Full Set (left and right) available.