I found this auction on ebay, and on yahoo at the 
same time.  Neither auction describes it as 
a "production cel" but they never say that it is 
not.
Take a look
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?
ViewItem&item=1175877365
and
http://page.auctions.yahoo.com/auction/54107051?
aucview=search