Rock Auto, Year One, Dante's, Classic Industries, etc, lots of folks sell weather stripping. Check out some of the venders on the first page. Classic Industries still sends out free catalogs that are fun to look through. It might help with your project.
If you are painting the car, you might consider new body bumpers for your hood, trunk, and doors. Also body plugs, firewall seals, etc. The little things can drive you crazy...hehe.
Here is a link to Dante's. I have good luck with him.
http://www.dantesparts.com/weatherstrip.html.,