Don't do it. All of your beneficial bacteria live on the surfaces of the rock. You'll immediately trigger a cycle if you remove it and replace it with new rock.
Looks like you can get them direct from LiveAquaria (ORA) as a single. Was looking at the gold/yellow one, as well as the blue. Anyone know if a gold and blue will do okay together in a tank?
My Yasha pops out where I can see him all the time, but I barely ever get any glimpses of the shrimp. I do hear the pistol snapping, so he must be alive in there somewhere.