Free shipping. It comes to about 25.68 after UKP to USD conversion and about 3% lopped off for your bank. Note, you may had an extra 3% if you don't have a card with no FTF(Foreign Transaction fee). They do accept paypal and i'm not sure what Paypals going US to UKP rate is.
Also, topcashback.co.uk has 2-3% cashback which makes it a smidge cheaper. They do accept US/foreign members and will deposit the cashback as a GC to your amazon.co.uk account and i think they pay other ways as well.
MODS: Please fix typo in the title