I spotted this makers' name on the footpath sign opposite the Sir Frances Burdett B and B on Derby Road (click to enlarge).
It seems that the company originated in Stratford upon Avon, then moved to Chipping Norton. It is now located just outside Buxton at Dove Holes!
It received its royal warrant in 1876 when it made metal plant labels for Queen Victoria.
The company is now owned by Leander Architectural (since 1998).
I found an interesting article here.