I'm assuming you're referring to the all aluminum or polycarbonate rolling ones, not the fabric.
There are several companies that make them, RollNLock, Retrax, Access for examples.
I know for a fact they make some for beds with toolboxes, I just dont guarantee its for our mini beds.
I cant give a for sure answer on the locking if not all the way closed. I dont believe they will do that, but I dont have one.
I hope that's a start anyways.