An FYI, the cloth covered harness I bought from YNZ is cloth over the modern PVC coating. It looks original but has modern protection. As Tim stated they are pricy. The one downside I've seen is because of the double insulation the wire is larger in girth than the original which can be an issue when trying to fit a wire bundle through a stock size grommet.

Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.