I don't know whether pied hognose snakes exist or not. I did a little looking around and came up with a thread on another site's forum from a couple of years ago. IMHO, as claimed heterozygous pieds have been available for at least a couple of years, pied hognoses ought to be showing up by the end of this year. I'd wait until pictures start showing up on the web before buying.

Paul Hollander
pied hognose thread