Does anyone know the best place to get a new weather strip for the windshield? Does GM still make them or should I look into a classic industries type place?

 

I'd call an auto glass place. It's one of those things that has to be made to pretty strict specifications, or your windshield won't do it's job. I've never heard of anyone having issues with aftermarket ones either. I'm 95% sure they replace it when they replace your windshield.