Thanks for the cel bag help (onion - n), but I 
decided to *custom* order one 100-box of 9" x 
10.5" 3mm polypropylene envelope sheets. I 
haven't gotten the quote back yet, but I hope 
it's not too bad.

If I have extra bags leftover, I'll pawn them off 
on eBay (j/k, heh).

Oh, I made the custom inquiry at 
pictureperfect.com.