Try posting on the GBWF.org board. Someone had some available not long ago, but the post for them in gone. If you have only seen them in photos they are awsome birds to see in reality. Pure japanese greens are tiny compared to regular ringnecks.
Thier is a nice bit of info and photos of them on the old gbwf board.
http://www.gbwf.org/phpBB2/viewtopic.php?t=7285&highlight=japanese+greenThe title of the post is Ringneck pheasants but Japanese green are in the same family so they basiacally apply to the post. The information on them and photos iis mostly on the 2nd and 3rd pagepage.