Either find the manual and the exploded view diagram or take the pieces to the dealer.
If you google your make/model and "parts", you should be able to find somebody that will sell you one.
If you have a weldor friend, nearby, they could repair it for you.
TT 2015 19RD "TheJayco"
TV 2003 F-350 "Montblanc" - Housebroken chore truck
Sitting in The Cheap Seats.
And proud of it!