A number of years ago I had WR #T4842. WR confirmed by letter that it was made in 1913 for Manton & Co, Calcutta. I recall that the gun had the WR name but not Manton's. It was a mid quality boxlock ejector, 12 Ga with 30" steel barrels, modest scroll engraving and the butt stock had some figure and had a straight grip.
Hope this information is helpful.