They come and go at the stores, and as
@DaveK mentioned they are not something any LFS usually wants.
It is well worth putting an order in with your LFS. If they are not comfortable with this idea, find a new LFS or bribe them with beer or gift cards. See if there is a DOA guarantee with the Mantis IF you pick it up right from the bag at the store.
I waited about 4 months for the right peacock, and it died after a year. I wish I had gone with something smaller and more interactive.