Silver? Silverplate? Pewter?

Hi everyone, I have this little round base with 3 feet on it and a simple handle for a little porcelain nut dish (no marks on the dish) which was my Grandmothers. They had relatives in Cornwall, England if that helps any. I'm guessing it was a wedding gift circa 1922 or so. It did have some tarnish most of which seemed to come off with silver polish, but there are still some dark areas. It has this series of stamps on the bottom and I can NOT for the life of me figure what any of the stamps mean. The only one I can say for certain is a capital scrolling "S". Any ideas?? I posted it both directions... as it seems like it could go either way...
Thanks for any suggestions or id's!
Cheerio,
Leslie

 

EPNS (silverplate) The small square has the maker's initials inside, but I'm having trouble seeing all of them.

 

Could the one box say
HW
LTD
?

 

A good suggestion, Bronwen!

https://www.silvercollection.it/electroplatesilverWZdue.html#WILK1

 

Gosh! I think you all might be on to something here! I couldn't even make out THAT much! Thanks so much! I'll do some comparisons tomorrow!
Cheerio, Leslie