I removed the vent window to replace glass and see that the run channel material is very worn. Where can you get new material?
Everyone carries those. just a felt U channel. Most places carry a door kit that has those, the wipers, vent window rubber , the division bar rubber and door channel runs.
You might wanna' send some business to our host, Classic Parts, as they also have the window channels, and the aforementioned 'kit'.