I wonder if this is of any use to anyone interested in matters Finnic? I've been looking for such a map for ages, and was delighted to find it in
Narody Povolzh'ya i Priural'ya, Narody i Kul'tury (
Peoples of the Volga and Urals, from the series Peoples and Cultures), published by Nauka, Moskva 2000, by N.F.Mokshin, T.P.Fedyanovich, L.S.Khristolyubova, which I immediately bought, despite the extortionate price of 1600 rubles. So why not share my joy with you all?
http://img220.imageshack.us/img220/1473/dubkeytt2.jpg
I coloured it in, as the original was a bit hard to read, and I suppose it's broadly accurate though I may have made a few mistakes due to the occasional ambiguity in the original. The beige areas are of course settled by Russians and Ukrainians. There's a few Mennonites and other Germans too, scattered around.