Yes, the barrel can be tapped and a choke inserted. It cost me about $70.00 to get it done including the choke and it took about 2 weeks, but I had it done in early February.

On the other hand, the Imp cyl that came stock on my ithaca killed a bunch of birds before I found a second-hand barrel in a pawn shop and had it cut and tapped. Just be patient and make sure they're inside 30 yards.