In terms of European countries, I'd definitely put the feelers out in Norway - the producers seem to love rewarding countries that get their own versions with visits. Think about it:
TAR Asia 1 establishes Malaysia as its base, the next US season (TAR 11) visits Kuala Lumpur
Brazil gets a version, the next US season (TAR 13) visits Brazil and features many of the same locations
Israel gets a version, though the country is on CBS's blacklist, the next full-scale foreign season (TAR Australia 1) visits it
Latin America's first season was run by an Argentine production company, the next US season (TAR 16) visits Bariloche
China... well, you know...
TAR Australia gets a version, the next US season (TAR 18) visits Sydney and Broken Hill
France gets a version, the next US season (TAR 21) visits it
Vietnam gets a version, the next US season after it finishes airing (TAR 22) visits it
That just leaves Norway, the Philippines, and the upcoming Ukrainian version. The Philippines is out (although depending on when it was confirmed the TAR Australia 2 visit could count as its reward), but Norway and the Ukraine are still possible.