my previous GN was missing the driver's side. at the time I couldn't find a replacement so I made a very convincing dupliacte out of some cheapo flexible plastic edging/trim material I found at a local autoparts store. I don't remember what is was originally supposed to be for, but it was basically the same stuff as the flexible chrome trim stuff that some people put on the edges of their doors, gas filler doors, etc. except this was satin black very close to the original finish on the black metal door edge guards. I used the passenger side as a go-by and trimmed a duplicate for the driver's door. tacked it on with a very thin bead of trim adhesive and you really couldn't tell the difference, and actually it was better than the original metal piece because it wouldn't dent and the finish wouldn't flake off.
HTH
Rob