A couple of points...
Counting the stars is a red herring. They mean nothing or, better said, there was no hard and fast rule. Sword collectors counted stars for years on decorated blades and hilts and it led to some odd, if not totally unrealistic dating.
Smart Dog is right about the lock but the earliest possible date is 1801/1802 when WK went into business under his own name. A date more like 1805 is more realistic.
It's an extremely nice fowler. That Eagle escutcheon is very nice and a feature often associated with Holbrook. I had a very similar fowler and, like yours, it was not marked with the maker's name. Holbrook was an excellent maker, one of the very best.
The importation of locks did not start until late in 1792. Until then they were under an embargo placed on military stores in 1775 so virtually all guns with English trade quality locks have to post date November, 1792.