727 Pump/TQ Hub Seal Leak

After having a 727 leak become increasingly large I decided to pull it. I do not see a leak from the vent hole, the perimeter of the pump cover or any cracks. The only place I could see it was leaking was around the TQ hub at the pump seal. The TQ is a Dynamic 9" 3000 above stall, I replaced the seal when I installed it two years ago.

Currently, I bought a new seal, National brand with a flange. I don't know the brand of the old seal. I placed the seal on the Dynamic converter's hub and it is noticeably less snug when compared to my old TCI TQ. The Dynamic converter hub is a couple of hairs smaller in diameter when compared to the TCI but Dynamic told me the difference is negligible. I cannot see what else is the problem and with the difficulty in pulling my tranny I don't want to put the Dynamic back in only to have it leak but I hate not to use it. I thought of sleeving the Dynamic but that might make it too tight of a seal and burn it up. I thought of a smaller ID seal but worry about the same.

Any ideas? Am I over thinking the idea of a smaller ID seal being a problem? Any ideas of how to figure out a smaller seal ID with the other dimensions being the same? I tried the National/Timkin catalog but had no luck deciphering it.

Thanks for any help.