Not a Brades Mistletoe cutter by any chance?
You should recognise the name "Brades" Dave - they were from your neck of the woods. My father was a stonemason & bricklayer. His trowel of choice was WHS (William Hunt & Sons) they established the Brades Forge. Here's a brief history.
The founder of the company, William Hunt, was an edge tool maker at Rowley Regis, near Dudley, Worcestershire, in the late 18th century. In 1782 he purchased the Brades Estate at Oldbury, near Birmingham, and established a new works there known as Brades Forge, or simply as The Brades. By 1805 they were also manufacturing steel on the site, which was now known as the Brades Steel Works. Around 1793, Hunt took W. Cliffe into partnership, and for a short period the firm was known as Hunt and Cliffe: this name appears in the company's first ledger, dated 9 May 1794. This partnership dissolved around 1803, and Hunt continued trading on his own account until 1809, when he took his sons into partnership and the firm became known as William Hunt & Sons.
In 1828 the company acquired William Edwards and Sons (incorporating the Eagle Edge Tool Company), and later the business of Bache Bros, spade makers of Churchill Forge, near Stourbridge. In the late 19th century George Heaton became a major shareholder in the company.
In 1951 the company amalgamated with Nash Tyzack to form Brades Nash Tyzack Industries, and later took over the business of Skelton. In 1962, together with Harrison, they became part of Spear & Jackson, who in 1967 also acquired Edward Elwell Ltd (they made the Cardiganshire or Aberaeron shovel for a time), all the companies coming together as parts of S&J by 1972. In 1985 S&J became part of the Neill Tools Group based in Sheffield, who still own the brand today.
Interesting isn't it? So my guess is it's a Brades Mistletoe cutter (a very rare tool by now & worth a bomb as an antique tool). I could be wrong of course, Dave's suggestion is also a good one.