I forget the brand name, but we have a bunch in the basement that we bought at Lowe's for my wife's business. They all said made in USA. Might try there. They are gray steel with particle board shelves.
These are the Edsal shelving units.
I needed some in a pinch, and went with two of these units put together as a wall unit.
I don't regret the purchase at sale price... But they are definitely lacking as a permanent solution. The OSB sags, so plywood replacements are going to be mandatory if you plan on having much weight on them...
The steel supports are also rather sharp, and flimsy.
I use the shelves to store a ton of various size empty coolers and pelican cases. Not a lot of weight at all... Maybe 50 pounds per shelf at most.
Im still looking for their successors!
~Tejaas~