International Orders can be made, but just not on-line. Here's an excerpt from the Frequently Asked Questions section from the above link:
Quote:
The online Postal Store currently does not provide international shipping for Postal Store products. If you wish to place an international order you can do so over the phone, by fax, or by mail.
For mail orders you can send your order to:
STAMP FULFILLMENT SERVICES
PO BOX 7247
PHILADELPHIA PA 19101-7097
Fax orders can be placed 24 hours a day, 7 days a week to 1-816-545-1212.
Phone orders can be placed by calling 1-816-545-1000. Hours of operation are 7:00 AM - 3:30 PM CST Monday - Friday, closed Holidays.