If you look at some of the question/answer threads on this photo, you will find people who have posted sources. Good luck.
Gregg
I photographed a house and they had a giant geode print like this on a large piece of acrylic. This would be a much cheaper solution. Find the image of the geode on my profile under the Beach Road North home.
186 Lighting Design Group - Gregg Mackell
Andrew Sherman Photography