Just travel with a firearm. You are by law required to have a lock that only you have access to and a hardcase around the gun, so you can travel with cases made out of metal with hefty locks that only you can open and if TSA needs to get into them they have to get you, they can't just pry them open.

And the fire arm doesn't have to be loaded and IIRC it can even be a flare gun, if you don't want to own actual firearm.