<div style=": rgb251, 251, 253;">
<div style=": rgb251, 251, 253;">You can buy a 16GB one on Amazon for £6.55. It's quite small which is ideal as you don't want it sticking too far out.
http://www.amazon.co.uk/gp/product/B002U1ZBG0/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1