Gravely 816 transmission woe(s)

[Outatimejb]

I just bought a gravely 816 lawn tractor with a bad transmission , it looks like most of the pieces are here but I can see the condition of some parts has me concerned.
This is the story The diff gears in the rear end broke it's all taken apart , just wondering if anyone knows much about this transmission or knows of a donor
Any help would be greatly appreciated thanks