Available from this shop in Spain:
From Punto Verna: Reproduction Jacob's Ladder
A much less expensive version available here (poly-wog to frog)
Amazon: BUY NOW Wooden Visual Illusion Blocks Science Educational
Classic versions of this toy available here:
Amazon: BUY NOW Jacob's Ladder Toys
The same ribbon hinge mechanism is used to make the "magic" wallet click here
Jacob’s Ladder Image Flip: with a twist of the wrist this reproduction flips back and forth between an image of Queen Victoria and that of Prince Albert with a satisfying click-clack sound. The earliest description of the ribbon hinge mechanism that creates this kinetic illusion of cascading blocks comes from a magazine article in Scientific American in 1889.