Hanno,
I have just had a harness made by Auto Sparks, for a Humber staff car. An excellent job and service. They sent it to me without the braiding to check against the vehicle and for any additions, I then returned it for final braiding. All cables are modern pvc with the original pattern braiding and all the correct colours as in the wiring chart. Cables of all colours are available separately. A few years ago they made one for a Bedford MW and it fitted perfectly.
I do not know if the Canadian / US vehicles use the same colour codes, ours are to a British Standard, each colour denotes a particular circuit, irrespective of make of vehicle.
Richard