are you talking about the sill plates at very bottom entrance of rear doors
or are you talking about the long vertical piece of vinyl trim that is the color of the interior,.....the only other thing that holds down carpet in the rear door, dog leg section is the weatherstrip ( door seal ),...as it goes on the metal edge
around door opening it also serves to hold down a 1/4 to 1/2 inch extra length of carpeting on the wheel arch, etc.
all of these can be found on ebay
and the door seals, new at bj's off road.
hope this helps.
dave in NC