Awhile back someone mentioned that National #327 O-ring might fit the bill. Haven't tried it but maybe someone else has.
It seems I read somewhere one time about using an o-ring. When I replaced all the gaskets recently, I just used that cork gasket in the retainer between the 2 washers and it was leak free until I had to remove the transmission and apparently when I put it back together this time, it went to leaking.
Kevin
