Have you tried Fleetwood Parts? They sell direct to owners.
Fleetwood Customer Service (800) 322-8216.
You can also order through an American Coach dealer.
There is an excellent American Coach Owners group on Yahoo - the AC owners are very helpful to each other on matters like this. Especially with older coaches.
2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL