Local pawn shop has around 10 1 lb bottles of opened powder pistol/shotgun and rifle, all felt mostly full, $8 each. No cans, all plastic bottles. None smelled off or had any other signs of deterioration.
The rest of the story:
I passed on the powders. I knew opened containers presented a potential hazard. I only currently use one of the powders (Power Pistol) which does not have a particularly unique appearence. There was also a bottle of Blue Dot, Clays, Lil-Gun, Ramshot (maybe Enforcer?), a few Alliant rifle powders, and a few more I don't recall. None of the powders were obviously mixed (flake and ball etc). While I don't think the guy that runs the gun counter would be stupid enough to mix powders, the pawnshop itself is on the shady side of town and is not what you would call well organized. They were recently shut down for a few days by the fire marshall, until they could get everything picked up off the floor so the aisles would be passable. I do have a chrono and may consider 4 lbs+ of something I use a lot of such as Red Dot that I could work up a load for and use for some time. Thank you for all the replies.