help needed on shoulder belts

[nu2-72]

As most of you know, shoulder belts for these trucks are more rare than the ultra rare 3 door burb.
Since shoulder belts are basically additional sets of belts, just bolted to the pillar,what other vehicles of the same era have the upper cab hardware that would make a set of belts? Anything out there?
My truck needs blue belts but I have only seen black shoulder belt covers. Were there other colors? If so, were they all black and dyed like dash pads?

Any help on this is greatly appreciated.