I just ordered some Crocs Nation Cayman shoes for my kids. They don't care that they have an England flag on because of the football, and are happy to wear them because they are English. They'll only wear them for playing in the garden with the paddling pool anyway.
I also used this code: PEP269VZ and got 10% off.
Postage and packing is £3.99 (if I remember correctly)