I meant to add, NASA invented a camera that uses radiation to make digital images. I think it was a MIT class that made a smaller version of of the NASA camera that was used to enhance the lettering on the dead sea scrolls. Maybe, the Smithsonian has something that could enhance the lettering on your flag, it wouldn’t hurt to ask. If they have something that could read the lettering, it would increase the auction value of the flag.
Happy Trails!
Tom Martin