Here is a USN one from our least favorite auction site:
The seller says: "Bought this in the mid ninties from DRMO in Hawaii, This might be the only NAVY mule. This mule did not appear to have ever been used off road when I purchased it. It still has the NAVY blue paint, however the paint is not great, The rollbar was done by the military and the only mods by me have been the electric start. "
You can barely make out the USN on the riveted plate. See pictures.
Goes without saying you should take the seller's claims with a grain of salt. People selling things aren't historians, they are sellers.