They are very rare. I have seen one at the Bronx zoo in NYC and Parrot Jungle in Miami.
I havent seen them in the pet trade, but that doesnt mean for the right price, they couldnt be found. They are huge birds.
Did ya'll notice the same thing I did about the beautiful St Vincent? They seem to follow the Amazon pattern of "never miss a meal." Those are some solid looking birdies -- might even be called "fluffy."