Does anyone have any info on these marks?

I have a salt spoon, could anyone shed some light on where it was made and when?
salt spoon front.jpg
salt spoon.jpg

This is an English sterling hallmark. However the lack of an assay office mark and a date letter make identification more difficult. The shape of the duty mark indicates a date of c1798. The lion passant sterling mark looks like London, although the maker’s initials suggest to me Joseph Goss of Exeter.