BTW, I have one of those dinguses (looks like a Lyman choke) and a Cutts on a Model 12. Once had a PolyChoke. I cannot recommend any of them. I used a spreader load. They were no longer readily available after the gunmakers started choking for plastic cup wads, so I first got a PolyChoke. Later had it replaced with a Lyman. The gunsmith (?) misread the order. I wrote" cut the barrel to 24" then install the choke." He misread and sent it back at 24" overall. This was on a Belgium Browning A-5. I eventually replaced the barrel with a Japaneese made barrel with screw chokes.
Jack
I guess I'm weird. I like adjustable chokes...
Too bad your gunsmith thought you wanted a self defense shotgun with an adjustable choke. I think I'd be looking for a new gunsmith.
DMc ; )
PS: Why buy spreader shotgun shells. Just mix shot sizes together at the reloading bench and you'll come out BIG $'s ahead.