Justin,

On this USPS link it states quite clearly that you can insure Priority Mail which is a registered mail package, for any amount up to and including $25,000.00 USD per package..........

I have NEVER had the U.S. Post Office question the insurance amount on the large numbers of guns that I've shipped with them for many years.........after all, as the shipper, you are the one setting the value on your package and paying for the insurance, not the post office.......


https://www.usps.com/ship/insurance-and-extra-services.htm

Doug