Have a look at
http://en.wikipedia.org/wiki/List_of_cattle_breedsThough Frysian cows in the 1930 were not rare in the Eastern European areas, the more common types were types like Ceskestrakate, magyartarka, czerwona Polska. In general: very local breeds So, for those who do go for the ultimate correctness, there are some more possibilities than just plain black and white if you want to create a eastern or central European atmosphere. For NW Europe, it's easy going with simple black and white.
For those at MasterBox: keep on going with these kind of ideas. JUST GREAT!!
I will certainly do one in a Ukranian setting.
Waiting for the next one!!