In my experience once you complete two Jackpot missions for PAM (on one occasion it happened after only one) and two missions to place the MILA for Tom you can then buy items from him made with the ballistic cloth. They start with the word "armored" whatever. Also from that point you can craft items at any armor work station. The better you armor skill lets you go up to ballistic cloth 5 I think. It is GREAT. I never looked to see if a perk shows up in my list though. Hmm.