This single is evidently quite rare, as the auction price below shows:
http://www.auction.co.jp/mem1/item/m...sp?LOT=1165143
I'd really have liked a copy of it, since it's my favorite Haruka Shimotsuki song.
MOONSTONE's site has a thumbnail of the cover (bottom of the page):
http://www.moon-stone.jp/kanren/kanren_ast.html