The only other example I know of is in the Willett Collection, Brighton Museum. This is my all-time favorite collection, but this dray men example falls short. Very wooden, isn't it? And something funny is happening above the inn sign, I think. And look at that lower hand on the right, grasping air. Hmm.....
I found this print in the NY Public Library. It is from Thomas Lord Busby's Costume of the Lower Orders of London, published in 1820. Surely it is the design source for John's dray men group?
PS: I erred. I do know of more than three examples of this figure group. I have two examples on record that are rather unattractive, probably quite restored. And Jonathan Horne's final exhibition featured a rather attractive example.