I have a silver table snuff box with London import marks and what I assume are German marks on the base. Can you help me please?

The Import Marks on the inner rim show 800 grade, the Leopards head for London and the importer which seems to be EC. That importer's mark is incredibly small, around 1 mm high. I've looked at it through two lenses and that's the best I can make out.

The Marks on the base are much clearer and well struck. The picture below is of one set of 3 marks which I have doubled up and rotated so you don't have to stand on your head to read the initials A.M.S

As always I look forward to your expert analysis.
Ian T