Thank you for the hitherto unseen print (by me). I thought I had seen 'em all, when I got a copy on loan of Boxiana, by Pierce Egan (1812). Sadly enough the great hero, Belcher was ruined by imprisonment for "disturbing the peace" and caught a fever in jail.
His life and early death, was a pattern for many a latter day pugilist.
I think Gentleman Jackson was one of the few to retire while the getting was good, and to make a name and living for himself afterwards. I think he was in charge of security for the coronation of George IV, and that must have been years after he retired. He ran a boxing school next door to Angelo's fencing school in Bond Street (I am more of a fencing fancier than a student of the gentle art of the London Prize Ring).
There are two fine books that you simply must read if you haven't yet, in which the Prize Ring figures largely: A. Conan Doyle's Rodney Stone, and Donn Byrne's Destiny Bay.