My New Service is in .45 Colt. Like yours, it had been re-finished.
Mine had razor-thin front sight and a teeny nick of a rear sight. It shot about 18" high and 12" to the left. After thinking it over, I finally bit the bullet -- it's been re-finished and it's not really a collector's item. I cut the old front sight off, soldered on a new one -- a huge slab of steel, 1/8" thick -- and zeroed it for elevation. Then I opened up the rear notch to match, doing most of the cutting on the right side.
I now have a beautiful sight picture, and she puts them right on top of the center of the blade.