Castlevania: Lords of Shadow: Ultimate Edition, PC – £9.26
To purchase digital games from Amazon US, use your UK Amazon account, and add a US billing address to your account. This address needs to be a valid US address, but nothing will be sent there, and you can access all your games through their website. Some card issuers may charge a fee.
Registers on Steam.
I am fairly sure that this is region free, but have not been able to 100% confirm this myself. I’ll update this post if I hear anything concrete.