Hi !
Staples 8"x8" brown cardboard 25 for 10.79 is about .44 each.
http://www.staples.com/08-L-x-08-W-x-06-H-Staples-Shipping-Boxes-25-Bundle-60080806-/product_693725
is this what you ship your 6"x6" in ?
Cathleen
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