We're working to get the game into European retail, but things have been very tricky in this regard. Right now I would actually recommend ordering it direct from Stardock (if you take the CD option, you'll get a retail box shipped to you) - especially given the currency conversion between the US dollar and British Pound.
For those in the former USSR, Snowball will be publishing Sins in your territory.
Those in Australia/New Zealand should look for the game from Auran.
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