Thing is, most materials like these are going to be in massive supply once 95% of the population is dead and there’s more resources available than anyone could ever use.
Copper and gold would be good for electronics, but survivor groups won’t be interested in that until they actually can make electronics, so it probably wouldn’t actually have any value until 0.5-1 year in, and gold probably wouldn’t be worth nearly that much.
I can’t think of any good uses for silver.
Rebar is pretty much just steel, and in a readily available shape at that. If the giant railguns come into common usage as point defence they might gain some value, but not 75$.
Batteries would be decently valuable early on, but would decrease over time to nearly nothing once they have some solar panels going on.
Kevlar plates probably would be worth a fair bit, but they’d also be fairly common what with all the dead soldiers and abandoned bunkers, so I don’t know what to think.
Aluminum is pretty handy, it’s price should probably be a bit higher depending on the size of the bar.
Not actually sure how ingame dollars convert to real world values so my comments on value might be off, but the rest stands.