Galleon - help with worn hallmark

Any help in identifying this gratefully received. I’m assuming it is attached to Iona silver so Scottish or made in Chester - as many pieces were.
There is also three dots - totally unreadable
2014-11-12 20.38.49 (7).jpg

This mark looks identical to one registered at the Edinburgh Assay Office by George Panton & Son Ltd, a Glasgow company.

Thanks! Very much appreciated. I’ll investigate further for dates.