Honestly Im not sure how to tell. I know alot of the PDI parts are stamped with the name but thats a guess for your parts. And the metal shavings Id say a no to. Ive never seen that in a gun and had it working properly. Maybe its just me but hey.
As for getting the receipts for the upgrades, good luck. Some people, myself included have done alot of work on their guns. And after years of replacing parts I know I dont have even half the receipts of all the parts that have gone into that gun.
I can list off every part but having receipts from 4+ years ago is a little beyond whats going to happen Id think.
Any how good luck with your search, hope you find what you need.