There was a Hussey gun for sale last year on Gunbroker with two barrels like the one described. I bid over 8k on it but ended up losing the auction. There was another Hussey hammer gun a yera ago at Jaquas for sale. I beleive I know where it is and the dealer who has that one. I remember looking at that one in person at an event. It needed some work and was quite heavy if I remember correctly.

Mike Proctor