Try another Agway or feed store. Or if you've got a chicken farm around they might be helpful. My Agway carried three grades of it.
Also available in Saugerties at outfit that sells fieldstone, tiles, etc. And sometimes Home Depot has it as a patio base. What you are looking for is crushed granite.

Hmm, It sounds a lot like the "stone dust" we've used for patio stones
and such, quite coarse and sharp really, the weeds LOVE it!
We get it by the yard at the nearby stone and gravel pit.

Thanks for the description, it simplifies things. Prefer
to get a yard or two than bags anyway, it's useful stuff.