Good luck- I think this guy is the hardest thing to find in the Rainbow Brite collection MIB after MIB Moonglow-
But scruffy versions turn up on a regular basis, and not for a lot!
Or you can custom make your own (This is what I did before I had the real one)
* Use a Barbie horse in the same pose, paint it white, re-root VERY easily by transplanting mane and tail from a plush Starlite, then carefully flock using craft flocking. Then all you have to worry about is the saddle (also easy to make)