I have one for hunting and I'ld like to make it a little more for home defense. I'ld like to get a shorter barrel 18.5" - 20", also tactical stock (not colapsable T-6 style but with pistol grip and shoulder stock also) I'm also considering a mag extension. Can anyone tell me where to buy these items. I have read that most model 500 stocks and fore grips fit the 835. I really want the shorter barrel. Any help would be appreciated.