I am seeking a lightly used 20 guage slug barrel for an old 1100 with rifle sights in good condition. The older 1100 is a 20 guage barrel on a 12 guage frame. I am unable to order from major dealers.
Good luck. I have been looking for large frame 20 ga. barrels for nearly a year but not for a slug barrrel. Your only source is used and most of them are either junk or cost more than new. Check the gun auction sites and forum classifieds regularly.
Also keep an eye on www.barrelexchange.com Have yourself comfortably seated so you don't fall out of your chair when you see the pricing. You might consider looking for a used LT-20 deer gun. A lot of target shooters like the old standard weight 20s, and in good shape they command a premium, but i like the LT-20 myself.