Diamond Crystal Kosher Salt---Where can I find this in MSP?
Lund's has it. I usually just get Morton's, but Diamond Crystal was the salt used by Thomas Keller in Ad Hoc at Home and the measurements would be off if I used Morton's. I found it at the Highland location, but according to their online delivery (or pick-up) website other locations have it too.
While I am a Morton's Kosher fan, I know this is a food service brand...you could just walk into a local establishment and offer to buy a box (D'Amico & Sons uses it for sure). I've done this with other ingredients and found it's often cheaper than buying it retail.
I'd also check other less-fancy outlets like Rainbow.