you should head over to Taro, they have some 
really nice cels of Mayuka. She's not all that 
hard to find ... in fact I remember seeing that 
exact scene within the last month, but I forget 
where :)

anyhow I know Taro has some 

www.taro-anime.com

you have to make an account if you don't have 
one, but it's no big deal