Since you are painting your car that opens up a lot of options. The problem with Flag mirror removal is that there are 4 relatively large holes in the door once the mirror is removed.
You'll have to weld in a piece(s) to fill those holes, but then you can start really putting anything on there you like.
Some of my personal favorites are:
Raydots
Talbots
I like the early metal flag mirrors too:
