Well, I have them in my tank, but only a few so far and I have not noticed any problems. We also have them in the store tank, in the SPS display they have insane amounts, if I go in first thing in the morning before anyone has started cleaning tanks, there are hundreds out on the glass.
As well as the 125 softies display tank, and haven't noticed any problems, but that's not to say that there are no problems.
Anyways I see the shrimp you want on the stock list every so often and my supplier is from the bay area, so I am sure all of your local fish stores have the same supplier, just not sure which ones use them and which ones don't.
I know at my store if someone ask me to watch for something like that I will put thier name and phone number on a "Wish list" and if I see something from that list on that weeks stock list I will call the person and make sure they still want it, then order it.
I know it works for my smaller town, in a place like Sac, or san fran you may need to know the store employees or owners to get them to do that.