I found this link through an email and I thought this would be a good deal...because it comes with awesome bags! I've purchased from this site before and it is legit. *EDIT* They also currently have free shipping, but I'm not sure how long that lasts.
2 X Ceramic Rings 500g/each for $9.99 Rings
2 X Activated Carbon 500g/each for $9.99 Carbon