There are a few vendors on the internet that sell parts for all brands of grills. Never seems to be reasonable in price.
I have made that particular part in my grills throughout the years. Its just a hood on the backside of the grill getting the flame from a lit burner to the next. Each burner supplies its own amount of propane by the selector you turn. I have taken the original hood from grills, measured it and then used sheet metal cut and/or put in a brake to proper size to make a new one. Guess one could use a vice instead of a metal brake,and by using a hammer and the advice given in lesson two of anger management and still have success in making the hood.
By looking at your photo and your concern of this hood falling off, maybe get a couple of sheet metal screws and bite into the landing area where they sit so they are fixed to something.
If you choose to accept this mission, we disavow any knowledge of your actions. ( Code for make sure the propane is turned off )
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