I need some answers on it. Is it costly? Is there a shop I can go to for the replacement or is it the dealer?

I would do it as a DIY project but its already leeking through the doors on the top when it rains or goes thru the car wash. If anyone has done it before and would like to share that'd be great.

 

Try jcwhitney and summitracing. They have weatherstripping replacements.