You probably already know that the hallmark is Edinburgh, 1976. I believe the maker is Jack Spencer (Silversmith) Ltd of Sheffield. They registered a very similar mark in May 1972 and I suspect that this is a slight variation on that mark which has been squashed down in height to fit the available space. You can find details of the registration at the Edinburgh Incorporation of Goldsmiths’ web site. The site requires you to register before you can use it.