Shuotian C.
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I had a smooth experience purchasing stamps at this location, which I used to send my postcards. They accept credit cards, and the stamps were priced at the standard rate of $0.68 for domestic mailing.
If you're looking to buy postcards, you won't find them here. You'll need to visit the souvenir shop in another building. However, be aware that the postcards are quite pricey, costing $5 each.