From US Post Office calculator:
Mailing Services (Show Dimensions) Estimated Delivery Time* Post Office Price
Priority Mail® International 6 - 10 Days $30.50
Priority Mail® International Flat Rate Box 6 - 10 Days $23.00
Priority Mail® International Large Flat Rate Box 6 - 10 Days $29.95
*Designed to be delivered in the number of business days specified for each service depending on origin and destination.
And USPS does not charge customs fees like UPS does - those can double or triple the cost of mailing.
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