I think people are overly paranoid if it comes to SN. Unlike N, it's not illegal to own, even in the UK. For the UK, it needs to pass customs and you're not allowed to import it, but you can just claim you've never ordered it. Most probably, it will just gets seized by customs anyway and you won't hear a thing about it anymore. Unless ofcourse you have a whole file of mental illnesses and suicide attemps at the local police station, that might ring some bells.
Use TOR when ordering if you're really paranoid so it can't be tracked down to your computer. But honestly? Just order it and don't be overly paranoid.