: Bring cash or a debit card; credit cards and personal checks are not accepted.
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: Write the recipient's name immediately to prevent anyone else from cashing it if it's lost. : Bring cash or a debit card; credit
Since you can't buy them online, here is the standard process for getting one at the Post Office: buy postal money order online
: This is your only proof of purchase and is required to track or replace a lost order. Online Alternatives