I can’t remember which brand carries it (perhaps both do) but I’ve bought sheets of styrene diamond plate from either Plastruct or Evergreen. When skinned with Bare Foil, it looks real:
This is my original 1960 GMC model. The first two pictures were taken with flash, the last picture is without flash:
The scale may be off by a tad, but it fools the eye into thinking it’s correct.