Amazon.com has 12-Pack of 16oz Ball Mason Wide-Mouth Jars for $8.47. Shipping is free with Prime or on $49 or more.
Note: Says "Temporarily Out of Stock", but you may still place your order and you will not be charged until the item ships.
Editor's Notes & Price Research
Don't have Amazon Prime?
I had just bought these two days ago for $18.
Amazon refunded me the difference
If you're not a student, there's also a free 1-Month Amazon Prime trial available.
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