I bought it a number of years ago from K7PED, I don't think he makes them anymore. You can make your own by using a actuator you can find on eBay. It is nothing but a worm gear, push pull device that is used for aligning satellite dishes. This one isn't the one used but it will give you an idea as to what to look for
8" Linear Actuator | eBay The rest is nothing but some aluminum welded together so that the actuator acts in fulcrum mode to push the antenna up and to pull it down.
