Need a gun smith to switch a Ruger barrel

[Overkill338]

I want to find a Smith that can switch Ruger barrels. I will GIVE them my .375 Ruger Alaskan, if they will get a 26" 375 Ruger barrel, and swap it onto my African receiver. I want to use a barrel for a Ruger American. The threads are the same as MkII and Hawkeye, but the American has a barrel nut.