Drive shaft output plug

Several years ago I replaced the ujoints in my 06 automatic. I had to heat the yokes to remove the nylon keepers and to get the cups out. Since then I have had a leak at the transfer case output. It’s not the seal leaking it’s coming out of the inside of the yoke. I remember reading somewhere that there’s a plastic plug in the output shaft that probably melted. I’ve never been able to find this plug in any parts description. I have to replace my carrier bearing so I would like to fix this also. Anyone have a source for this plastic plug?

 

I'd probably just pop said plug of a bit, clean, and put some RTV on it and push it back in... no force there so not going anywhere.