It would be simple enough to get your average impact socket and bandsaw a ring or 3 out of it, mainly to get the internal hex. Bonus points for cleaning it up on the lathe but a flap disk or file would easily get the rough edges smoothed down.
Weld a tab to it in whatever configuration you need, best not to fast cool the weld to maintain strength.
As a backup against a 1" sq drive mpact use might need something more serious than what I have in my head......