Express 1 - Priority Mail Express Shipping Receipt

We recently have had a few cases where USPS has not delivered Priority Mail Express Packages within the guaranteed time. The local PO will not refund shipping without an exact amount paid online. Unfortunately, just reprinting the label will not work since the label says "US postage and fee paid" and does not give a dollar amount. I have tried overriding this option on an order specific basis, but this doesn't work after the original label was printed. Can you tell me how i can print an "official" receipt that shows postage paid and the tracking number for Priority Mail Express shipped via Express 1.

Thanks!