When this game first came out, many people were wanting to put in every country in the world into the game, and wondered where to get flags of said nations.
Now, I don't know if this is still a problem, but while researching something for college, I stumbled upon the single greatest site in the universe for national flags and a country list, the flags of which are all a consistent size and can be scaled down for the game's purposes.
The CIA World Factbook. Who knew?
Anyway, I figured I'd provide the link here. One of these days when I'm less busy, I'll just download all the flags myself, ZIP 'em, and post 'em here. Because I care like that.
https://www.cia.gov/cia/publications...ook/index.html