You can export subscribers by going to Subscribers > Export Subscribers:
You can export to a file, or to a new mailing list. Choose which fields you'd like to export, as well as the scope of how many:
You can export subscribers to any of the following file types:
You can perform an "export then import" by choosing "New List" under Format. This will take you to a new pop-up:
As expected, all subscribers under the "How Many" scope will be instantly imported into the new list.