Lloyd's Lists
https://catalog.hathitrust.org/Record/000549597
This takes you to high quality scans of all the Lloyd's Lists from 1741 to 1826. Not infallible as there were thousands of ship movements every week, but may help you find the ship that carried your cover in this period.
7 Views
Certainly not infallible and nevercould be, but well worth a look.The clarity of the pages is far superior to those found on the British Newspaper website, but you will have to use that after 1826.