The one you have pictured here is the Double Think Binary Ring. To my knowledge it never went into production and only 4 of these (as prototypes) were sold directly from the inventer. I have 1 of them

See this thread:
viewtopic.php?f=4&t=20625If you want the other puzzle, the Double Disc, you can still find them on Amazon for really cheap (under $6!). I do recommend getting one.