Winchester Black Shadow 1300

I'm tried to make my Black shadow a more home defense type of shotgun by getting a Choat pistol grip stock and a shorter (18" ) defender barrel. But as some of you may know the barrel ring on the defender barrel is far forward because the Model 1300 defender has a 7 shot tube. What can I do? Buy a 1300 Defender and have a spare barrel?....try and sell the defender barrel and use a 24" slug barrel that I also have (along with the original 28")? Is it possible to put a defender mag tube on the black shadow?

Thanks in advance