MaxTool via eBay offers the Durostar Eco-Shredder Chipper, model no. ES1600, for $159.99 with free shipping. That's the lowest price we could find by $59. It features a 2-horsepower motor and three-cycle shredding.
I have two purchased about 5 years ago. They work fairly well for small branches less than 1/2", vines, and dried leaves. The weakest link is the branch tube. Where it joins the outer wall of the grinding chamber the weld is less than satisfactory. I have had to weld this joint many times, the first machine to fix cracks in the tube and the second machine to prevent these cracks in the first place. The other problem is the amount of leaves that you can grind at one time. Not a lot but you can feed the hopper fairly quickly in small batches. Any rocks or gravel you drop inside will chew up the cutting blades. Designed for quick cleanups of small amounts of yard debris. Costs about ten cents per hour to operate.