http://www.smoothdrag.com/ is the home page for the company. I believe you can order straight from them. Get the extreme smoothies or the newer carbonex ones.

http://www.hatterasoutfitters.com/ also has them and all kinds of replacement/upgrade parts for abu reels. Listed under reel candy.

If I remember right, the newer abus have a better drag than the older ones. The old ones leave a lot to be desired.

Andrew