I've found a way to frame a cel perfectly without 
paying high costs of professional framing. 
However, please keep in mind that if you have a 
vintage cel or a very high priced dream cel, you 
should really think about having it 
professionally done. Hell, if you're going to pay 
$1000 for a cel, spend the extra $100-$200 to get 
it framed professionally. Anyway, here's the 
links:

Perfection Distributing- These guys 
sell glass wholesale. Personally, I've seen what 
acrylic looks like framed and I prefer glass. If 
you are carefull in hanging the picture, you 
shouldn't have to worry. They sell pre-cut pieces 
of UV resistant conservation clear glass at great 
prices. $5.49 a piece for 11x14(sells for $16 a 
pane at Aaron Brothers and Dick Blick when it's 
in stock) and $6.89 a piece for 12x16! You can 
order as much or as little as you want! No 
minimum purchase and they will ship to anyone.

Archival Suppliers- They sell every accessory 
you could imagine. Every kind of glove, cleaning 
solution, dry mounting corners, backing boards 
and mats pre-cut
By my calculations, you should be able to mat 
and frame as many cels as you like for around $23 
a piece! Hope this helps.