I when out and looked at that long hinged pin on my tractor, 1957 TO-35.
It looks more like your new bolt. The grove at the non clip end is where your chain clip goes that keeps the pin connected to the tractor.
the other end has the hole for the locking pin.
you have my interest here: How did you break the end off that long hinged pin?????????
over the years I only used that long hinged pin to support the hitch stabilizers bars when I use the cross bar hitch or a seeder or anything that does not require to be lifted up/down, but I want it to stay at the same height.
then lock down the lift lever, so I do not hit it with my foot and the lift arms go up and bend the stabilizer bars.