When you need brakes for yoru trailers, can you buy just the shoes? I have a Big tex trailer with 10" Dexter axles and i can only find assemblies not just the shoes. Napa, Oriely;s, farm & Fleet, only seel the assemblies. Cetainley someone else has had this problem? You can buy every other component separate, why not just shoes. Is there a brake shoe that universaly fits these assemblies?