Just go to your local hardware store and purchase the orange fiberglass driveway marker rods only a couple of bucks. These are solid fiberglass not like the hollow ones that come with your shack. Remove the broken rod and heat up the metal ends(they are only held on with hot glue of some type) pull them off. Cut the new rod to the same length then reheat the ends and push them into place. I always carry a spare rod in my shack bag quick simple cheap and better than the one that come with your shack. Good Luck
Ross