Hi, Good luck with your Mortimer rifle. The lock and stock are worth much more than what you paid for it. Getting a 1" X .54 cal. barrel is easy, and turning the barrel to fit your stock is easy as well. Mark Lee's browning solution from Track of the Wolf will finish your barrel close to the finish of the original. If you get a breech plug slightly larger than the original, will be an easy fit. YOU are one lucky stiff to get the stock and lock for $50..........hell, I'll give $51 dollars and I'll even pay the shipping. Now that's a deal!