Lol, MILSPEC doesn't mean much and "military grade aluminium" is a very broad statement considering the various applications it can be used for in the military. They have specs for everything down to their brownies. For all we know, Ford's MILSPEC aluminium could be the stuff used for military aluminum food trays.
But wow that final repair number. If the body panel every gets damaged it's going to be a tough decisions. Do you pay for it or leave the panel as it at that price? Unless you have the full amount out of pocket.