Fender Tag Screws
...although your larger screw doesn't look like correct proportions to me.
Hmmm
All that I have seen, including into the late 1980's are the same size and the heads are taller than "common" screws.
The Phillips "slots" do take up a lot of the head, like the small screw in your pics.
My vote-
Your small screw is original.
Large screw is a replacement.