Prama, The 10miu ones if you get overnight postage cost $32 for 10. Jodie also has the 20miu ones - I am not sure what price they are as I am too anal to wait that bit longer! The 10miu ones come in a plastic casing and they can be kept for posterity! If you can't already tell I am a fan too.
Good luck with your testing - hoping it's a for you!