Ih 800 planter seed drum drive gear box issues

[Joshbraman]

So I have an issue with my drum drive gear box. My input shaft has a pretty good groove worn into it and I see the inside bushing( I think its a bushing). Is severely oblonged. I was wondering if this is actually a bushing or actually part of the aluminum housing. Also can you still get replacement parts for this gear box or do I just need to find a good used one. Also is there a parts diagram for it anywhere. I looked online and its just labeled as gear box in most of the parts diagrams I see.
Thanks for any help

 

[fastfarmall]

The seed drum is ground driven right,the gear change/speeds, and seed drop count guide was on the planters somewhere or in the book, is all i can remember !!!