Find a good gunsmith. If you cannot find one, Scott Null at S&S Sporting is a Master Gunsmith, has a heat treating oven, is a master machinest and could make one for you that would work 100%.
His prices are reasonable and he will not loose or damage your shotgun.
He can have it picked up at your house by Fed-X. Just package the gun in a good case, double wrap it with cardboard. He has had thousands of guns shipped to him over the years and Fed-X has yet to loose one. A couple have been misplaced by Fed-X, but they have always found them. It's rare for them to misplace one.
Properly packaged, it will not get damaged either.
His phone # is 208-313-1570.
I'm a retired gunsmith, was a darn good smith, Scott is the best I've ever seen. Expect at least 3 month wait, good smiths are always backed up. If you find a smith that will have it back in a week, he is most likely not a great smith unless he is doing you a favor and putting yours ahead of other guns.