I had an an old(70/80s) Winchester 1200 shotgun given to me, like this(this one's in way better shape). But it's in good working order. I'd like to make it into a tactical shotgun(like the pic below) for home defense and to replace the beat up wood on the current gun for looks. Problem is, it's a 16 gauge. Hard to find parts for it, it seems. As far as the stock and forearm, it's all the same, right? A tactical stock/forearm will fit any gauge... 12, 16 or 20... as long as it's for a 1200, correct? Or am I wrong? I've found tactical kits for the 1200 online. But they always say 12ga, I assume b/c it's the popular gauge. ??? And I'd really like to find a tube extendeder to increase its shell capacity... where could I find one for a 16ga 1200? No luck anywhere at all. Also, the barrell... I'd like to shorten it to the shortest legal size. Can I just buy a shortened 16ga barrell? Where? Again, no luck online. I'd like to keep the original and not cut it. I want to preserve all the original parts so i can put it back to original. If I HAVE to cut it, is that possible? Will a gunsmith do it? Also, I know a 16ga is not ideal for home defense, but it was free and it's what I have. But it's simply too unwieldly in it's current form(mainly the long sport barrell) for home defense IMO. Something like the pic would be great. As well as being able to preserve the original parts. Thanks a lot!