Somegeek,
Sorry to hear about your incident. Goes to prove that "stuff happens" and we should always be careful.

An "idle" or "throttle" lock is a good idea, but you don't need to spend a lot of money to buy an expensive radio to do it. Sometimes in this hobby we all have a tendency to "overthink" something and overlook the easy way. All you need is a good ole #64 rubber band. I know that almost everybody has a bunch of these left around from our training days. Anyway, take the rubber band and "tie" it off on the handle on your radio. Then stretch it down the backside of your radio, up under bottom, and up the front side of your radio. Then loop it over your throttle stick. Viola, a throttle lock. The rubber band will hold the stick in the idle position until you are ready for it.

Hope this helps

Ken