I can’t help with what you really want to know, age and maker, but I can confirm that it is silverplated - the EP and NS together stand for electroplated nickel silver. RC are going to be the maker’s initials, but I don’t have a name to go with them.
Thank you for your reply!
One more question:The numbers on silverplated items usually refer to the designnumber or mean the thickness of silver or mean age or mens something else??
The numbers normally seem to indicate a design number. Plate quality is often shown by the fairly meaningless “A1” - meaningless because there is no standard to work to. Elkington’s plate normally has a date code and I understand that Huttons may also have used some sort of date coding, but I don’t think any others did so.