I've got two 1100's that I'm setting up for 3 gun. One is a 12 ga 26" barrel w/ IC choke. The other is a 3" mag. I'm looking for a 21-24" barrel rem choke chambered in 2 3/4 that I can put a full choke on. If I keep the 26" bbl ,how much should I expect to pay to have it threaded for a rem choke? Also, at 26" should i put a full choke in it too? Thanks,