Is it possible to buy just the puck advance motor? Hate to buy the whole thing when that is the only part bad
You can purchase it from Yard & Pool. They have almost any part you may need.
Generator Motor (http://www.yardandpool.com/bradley-smoker-replacement-generator-motor)
You can also call Bradley directly. Parts cost a little less, though they will make you go through some troubleshooting. They also tend to be generous with not charging for parts out of warranty at times, IME.