I guess I learned to cheat on finding photos a long time ago. When looking for display type photos, I go to auction sites. The cheat is years ago, my das was an auctioneer and even them in big items that he would we would take photos and send photocopies out to people who expressed an interest.
When I found that photo, that part is what I feared was broken in looking. While it could be replaced, my guess is that this is not an unbolt and install a new part. (I could not see that much detail in the photo.) My guess is that it is a portion of the cast of the housing. Normally, I would suggest a welder (he needs to know his stuff as there are processes to adhere to for welding cast) but I fear that the broken off piece may be history. And this area will receive a lot of pressure from normal hitch use.
If it is part of the cast of the housing, between expense of the housing, even if you found one scrape from a scrape tractor and feel comfortable changing everything out yourself, you will still be into the tractor for more than you could buy an open station of the same HP in my opinion. Lots of work and seals bearings and such that I would want to replace as I switched axles from one housing to a different housing.