Paul,
There was no original external weatherstrip for door glasses.
There was a strip of rubber stapled to a stiff card/fibre carrier on the inside, attached with trim nails to the inside top of the door underneath the metal frames. It wiped the window as it descended/rose and, presumably, minimised residual moisture from inside the door passing into the car.
It does not appear to be shown in the spare parts book. Effectiveness at keeping damp out of the car would depend on the several large apertures on the inside of the door also being sealed with a polythene membrane under the door card.
B…..