This is just about the rarest and most expensive damsel in the aquarium trade, with prices about $35 per fish. I checked the common online sources, and they were either not listed or listed as out of stock. This more than likely means you're going to have to keep looking until you find some offered for sale. I'd also make some posts in the WTB section of most reef forums.
This brings up another question. Does it need to be Starckii Damsels? There are many other species of damsels out there with similar colors that are lot less expensive. There are also similar colored dwarf angles. You would have a lot less of a problem acquiring those species.