Looking for a weatherstrip for a Ford Focus

Besides a Ford dealership, do you have any suggestions as to where I can purchase a “driver’s door weatherstrip on the body” for a 2013 Ford Focus SE? Thanks.

You can check local body shops but why not the dealer so you can get the correct part . I did a Google search and the seems to be a lot of places that sell the weather strip but what if does not fit like it should .