I believe that they are Sheffield and 1805 because of the B with the crown, but not completely sure.
The makers mark seems very poor. I would very much like to know a little bit more about them. They did come with two glass inserts but they do not seem to fit and therefore I think a rather bad later addition.
Any help would be fantastic.
One of the pair:

All the marks:

What I think is Sheffield 1805:

The makers mark:
