http://www.soffseal.com/14%20Universal.pdf
E1723, E725A and E401 work fine, but for the price, my favorite is the D
shaped seal that Richard Rodrigues sells. Someone may have his new
e-mail address now that he moved up to Mariposa and can chime in,
otherwise I can find it at home for you.
Use Super Weatherstrip Adhesive from 3M to attach it. Contact cement
and the peel and stick tapes fail quickly.
Best of luck,
RJ
VintageAirstream.com