Try searching on the term "Balkan" at JC's tunefinder (
http://trillian.mit.edu/~jc/cgi/abc/tunefind). Quite a few of the hits seem to be in G/C friendly keys, and there are some 4/4 tunes. Also, some entertaining looking things in 5/8, 9/8 and so on. If you try by country (Albania, Moldavia, Serbia, Croatia . . . ) you can find still more candidates.
All can be downloaded as midi files.
And if something's in the wrong key, most ABC players will allow you to tweak the key to something that works for you.
Let us know if you find any good ones!