We would need to see the pistol or know what every component is to be able to guess when it might have been rebuilt by the military. You look for the latest production parts, and you know it was after that date. Different types of phosphate finishes were used before and after WWII. The "green" Parkerizing sounds post-WWII to me...possibly even a shake-n-bake oven job done by Bubba.

Photos might tel us more.