Available from Radio Guy.
Here's the seller's description:
This was not a Halloween or child's toy costume. This is an original METALUNA headpiece worn by actors. It was used outside theaters to promote the 1955 classic science fiction movie "This Island Earth". It's made from a early rubber and is very fragile... so almost no original examples still exist. In fact I know of no other mask in existence. There is some edge cracking but the colors are still bright and makes a striking display. You'll never see another. $950.00