Yes both of these items have RP for Robert Pringle & Sons as the maker’s mark.
The spoon has a Sheffield Assay mark; I cannot be 100% sure about the date letter from your picture, but I think it is “u”, for 1912, although it may be “n” for 1905.
The goblet has a London hallmark; once again the date letter is a “u”, but for London this means 1935. This hallmark includes the optional jubilee mark which celebrates the 25th anniversary of the reign of George V. The mark shows King George and Queen Mary in profile.
I note that the goblet has suffered some damage so the value may very well be not a lot more than scrap value, especially as scrap silver has increased in value recently. If you Google “scrap silver calculator” you should find links to sites which will allow you to calculate the scrap value - remember that it is .925 standard.