Seal between 727 Dipstick and Tube

Simple question I think, but all searches bring up dipstick tube to trans housing sealing. I am looking to find a new seal that goes on the top of the dipstick to seal to the tube. Current one has silicone remnants on it, so I assume leaking had been a problem and the seal is pretty hard. Can I purchase a new seal only? And, where? Thanks.

To my knowledge that seal was never offered separate from the dipstick.

That would explain why I cannot find one. I’ll look for just the dipstick (no tube). Thanks.