Most dents in the outer skin require replacement of the alum panel effected...
This process ain't cheap, and involves knowledge of your Airstream's construction - Beware of any shop that hasn't been involved with this type of repair...
The only Genuine AS Northern Calif dealer is 'over the hill' from you in Los Banos -
This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.