The next issue is odd ammunition types.
It would be interesting to know if the US manufactured uncommon rounds (not for US modern equipment) such as 37, 75 and 90mm for export. Those shipments would have been locked down at some point.
I have always wanted to work the
Rock Island Arsenal into a T2k scenario as it seems likely to survive in some form. Maybe they use their production equipment to make these uncommon rounds and the PC are somehow tasked with moving them overland (or down the Mississippi).