I agree. I can tell you from experience that trying to find a .455 barrel in decent shape is very difficult and expensive. I would keep the .455 barrel and shoot something else. So many of these guns have .45 ACP barrels in them that to find one with the correct barrel is pretty lucky; regardless of how it got there. As long as it is the correct barrel on the correct gun and would have been a match back in the day you are ahead of the game.

The barrel on any 1911 is so easy to change that to have any 1911 this old it is probably impossible to determine if any barrel that is currently in it is the one that shipped with the gun originally. Especially in a military issue gun since they could have been replaced multiple times during its service life. Even with rifles or other, if you have the right gun with the correct barrel for that year and type and it looks right and has similar wear and is a visual match, then that is pretty good. It might have been repaired at one time but hard to tell unless it is the type of gun where the serial number is stamped on multiple parts thus allowing you to match numbers and have an all matching gun. But not on these.