FredC:

The new 1903 "Springfield" (banded) front-sights are probably knock-offs that are made in China.

There seem to be lots of beat up originals floating around that could be rehabilitated with some file work and refinish.

I will have to get the old vernier out, later, and measure some parts to answer your questions on dimensions.

(FWIW - I don't mind 'tinkering', gambling, and experimenting on parts that are basically wrecked. But, filing on a nice new $200 barrel .... that's serious money)!