Hallmark Help - Exeter, England???

I have been clicking everywhere silver-related, and even bought a couple of silver books - can’t find this pictured anywhere, but from my reading it seems the castle hallmark - one tower, not 2 or 3 - is from Exeter, England, sometime before the assay office closed in 1883. Can that be possible? I am a beginner. My guess at Exeter may be waaay wrong. Please check my photos, any comments appreciated.

Thanks,
Chris
P1020476.JPG
P1020477.JPG

Well it’s not an Exeter hallmark - they didn’t use that smbol - and I would guess it’s plated, having no date or silver grade marks. Not much help to you though! :frowning: