The brass rivets came today from Midwest Military.
I measured them and did a test on an extra plate that I had.
The head diameter of .215" and shape are right on.
I was concerned about the shank dia. of .120" because this is .030" smaller than the holes in the data tag mounting plate.
Until the very end of the rivet setting test, I didn't think that they would expand enough to work.
The last final hits with a blunt center punch expanded the rivet tight enough that it held firm. The rivet is flush with the back of the plate and looks just like the originals.
Due to the sloppy rivet fit of the rivets in the holes when starting, I am going to glue the tags in place first to prevent them from moving and getting crooked while riveting.
Midwest Military gives you 30 rivets, plenty of extras in case you goof.
I need to find some brass blacking solution to age them a little.