If you need a GM vehicle part you might want to check NewGMparts.com
http://www.newgmparts.com/partlocato...?siteid=213815
I recently ordered the rubber weatherstripping for the side entry doors and the front passenger door for my 1997 GMC Savana. The weatherstripping on my van is sticking out from under those doors and I figured I'd better get them while they are still available. I haven't received the parts yet but the customer service has been very good so far both on the phone and in email.
Prices were better than what I was quoted by GM dealers in the U.S. and Canada. I was not able to find aftermarket replacement weatherstripping for all three doors.
Part diagrams make it easy to pick the part you need. Example:
I will update this post after I receive the parts.