Help identifying a mark

Hi. I am having trouble finding out anything about a teaspoon i have. I cant identify the maker, the assay office and therefore its age. Any help would be greatly appreciated

This is a York hallmark. EJ is Edward Jackson and the date is 1819. York hallmarks only rarely included the town mark and here the crowned leopard’s head is also omitted. However the form of the date letter is unique to York.

Phil