You can get the nationality mod v3.0 at Serg's site.
http://web.telia.com/~u18230645/
Also, it has already been included in RUb, IUB, and HT.
Some of the new flags are Albania, Argentina, Belgium, Bulgaria, Colombia, Croatia, Czechia, Denmark, Estonia, Finland, Hungary, Ireland, Latvia, Lithuania, Mexico, Panama, Portugal, RSI/Republica Sociale Italiana, Slovakia, Spain, Turkey, Yugoslavia, as well as Red Cross flag.
The flags are currently in low res, but as I said earlier, they are currently being worked on...