[buymycards]

Go back to the PO. Don't talk to a clerk. Don't talk to a supervisor. Talk to the Postmaster. Tell him/her that this item is in his PO and that you expect him to produce it. Have him talk to the carrier who made the scan and tell him that you want the carrier to reimburse you for the cost of the card plus the shipping.
Tell him that you don't want to file an insurance claim and that you want the package, not the insurance. Be civil, but be firm.

Rick