The gun is beautiful and you are blessed. Over the past few years two gentlemen from these parts made me a true believer in all things Mullin (I think his brother John is included but I've not seen any of his wares).
So I fell hard and now own two Patrick Mullin creations, a 10 gauge muzzleloading shotgun and a 10 gauge breechloading shotgun with a Jones type underlever opener.
The craftsmanship is light years beyond reproach and I love them. You've got something special there, and as bsteele mentioned, 14 bore is really tiny for Patrick "Waterfowler" Mullin, at least from what I've read, which is limited to not a whole lot of material out there, after all.
