Silver hallmarks on 3 piece tea set

This tea set has both a set of hallmarks on the side and the word sterling on the base of each piece. (The tray is an unrelated Wallace tray.) As a newbie, I’m puzzled because the rampant lion would seem to indicate Scotland, but the word Sterling underneath would indicate American. It’s a gift for my wife for our anniversary, so I’m curious to know more about it… Any help would be much appreciated!! Thank you!
tea set hallmark smaller.jpg
tea set photo smaller.jpg