My brother looked into getting a Czech Wolf Dog but they are quite expensive and hard to find in the UK. I remember doing a bit of research with him at the time and seem to recall a snippet from the Dangerous Dogs Act in this country that Wolf Dogs have to be at least 7th to 9th generation crosses before they could be sold legally. Apparently you can't fully trust a wild wolf or a first or early generation cross. I could be totally wrong now as rules and laws change all the time.
They are stunning looking animals though, that's for sure.