http://www.economycandy.com/store/category.aspx?SID=1&Category_ID=76&
This place sells UK sweets in the US. I highly recommend trying a Double Decker, one of my personal favourites. Hefty bar of soft Nougat on a Crispy cereal filled Base, covered in chocolate. Simple, but awesome, the Peanut version is even better.

Try "Boost" aswell, very nice.