It depends on the size. For example a 2 pound box about $23.00, 1 lb. $17.00 5-6 pounds $60.00
USPS Medium Flat Rate Express International Box (5"x7"x4" box @ 3lbs) is roughly $28 to $38 USD, depending on destination location in the UK. You can get an exact quote at USPS.com. My quote is just a baseline for a generic medium flat rate express international box with base damage/loss value of $50.
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