Well, I finally got a quote back from 
PicturePocket.com.  They can make 9" x 10.5" 
sleeves (3mm polypropylene), but not in the 
minimum quantity I wanted.  The minimum is 1000 
bags for $165 (16.5 cents per bag).  Too bad I 
don't even have close to 1000 cels (let alone 
100).  I'm considering some other options, but if 
anyone wants to help me finance this (like 9 
other people for 100 bags each), let me know.  
Later.