Yes, there are cels used in Houshin Engi, like 
Samurai Spirit cels, extremely small quantity 
were avaialble through lottery and drawing (I am 
still searching for the person who won the 
Raishinshi cel in Tokyo during Summer of 2000), 
in the past 2 years in Japan, I have only seen 
around 10 Houshin Engi cels, this does not mean 
more will not be available in the future, they 
may get released at any time, or they may not 
ever get released at all.

>Is that a reproduction cel or a real one?

We only display actual production cels on our 
front page always, it is the actual production 
cel used during filming.

I will post more Houshin Engi cels future update.