I ordered mine straight from my hobby shop

Here it is at HB's site

http://www.hotbodiesonline.com/products/en/66539.html

5 bucks, and it comes with bushings, just take the bearings out of your .5 one, and your set. It is alot smaller then the normal one, Thats what you use the plastic bushings for that come with it so you can move it up. And have a nice shot at it with your servo

If you need a pic, LMK