These are the daddies for intake fans - http://www.overclockers.co.uk/showproduct.php?prodid=FG-004-SV&groupid=701&catid=57&subcat=4
Why would you care about direction if it was an intake fan, it's not like the air can blow through the metal. For exhaust fans maybe, but with low CFM like that I'm surprised the air it's sucking in even makes it through the case.