From your pictures it is still hard to tell what you are looking at.
If the sealing rings have worn a groove into the output support, that could be normal wear. The play that you measured between the governor is just manufacturing tolerance imho. There is nothing there that should wear. The governor assembly just controls your hydraulics to to the trans when to shift. It is not a load bearing part.
I am waiting to see you inspect the roller clutch bearing and the journal of the output support where the low/reverse drum spins to see if there is damage there.