Help Finding A "Private Collection"

Found the perfect dress but was told that it was a private collection and could only get it at that dress shop. They were pretty rude to me and would love to give my business to someone else but really love that dress. They said it was private collection 18763. But then they told me that they could order it in a different color if need be, so they are getting it from somewhere. I really want to find this dress. I also have pictures of me in the dress if it will help any at all. Let me know, thanks