Hi
It could be the Palermo eagle imprinted only partially.
![Image](https://i.postimg.cc/pyY8TPVh/Senza-titolo-1v.jpg)
This type of high-winged eagle was used from 1715 to 1826 and possibly beyond. Most of the time it has its head turned to the left, sometimes to the right, often it is crowned, sometimes not.
For comparison, I put a Palermo hallmark from 1806 under yours.
In this case, obviously, the other mark would be S.M and certainly not W.S.
Often, in Palermo silverware there is also the date. Try looking for it.
Best
Amena