Click "Local" on Coupons.com, then "Change ZIP Code". Enter 60120. Click "Coupons" (at the top of the page), then select "Household". You'll see it in the listing of all the coupons.
Maximum ONE REBATE PER HOUSEHOLD. Not worth my time and effort for $2.50 after stamp.
IF you have a Costco membership, refills are currently slightly over $11.