Trim pieces in front trunk area

I am a recent F-car owner and since I have had the car, I thought that the front trunk looked a little unfinished with the raw edges of the bottom carpet exposed on the vertical surfaces where they lap with the carpet coming from the top. I noticed in pix of others that there are trim pieces covering the lap. What are those pieces made of and what to they look like close up?? I suspect they are not available any more, but if I could get a look at one I could probably find a reasonable substitute. Thanks!