I can't speak to the specifics of your '46, but it would seem that the tracks should be a reasonably available piece from a modern supplier. The track merely has to be of the correct width, and can be shortened for your application. You might check with a local windshield place and get their take on it. You may be able to bend your own tracks with a brake and some proper guage material. Take a piece of your damaged track to a machinist/metal shop and see what they think. It's straight and narrow and has an extra flange. How hard can it be?
