Matthew Winterbottom has done a great deal of research into this set of sconces, see Royal Treasures A Golden Jubilee Celebration, London, 2002, p.255-256, no.175.
Besides the present pair, known as the 'Oken' or Acorn sconces which were made for Queen Mary of Modena and her husband King William III between 1686-1690 for Whitehall Palace at least 12 survive. They include a set of four in the Royal Collection, capped with Royal crowns and applied with the cypher of William III, which were gilt and improved by Rundell, Bridge and Rundell in 1816 at the request of the Prince Regent, later King George IV. In addition, a set of eight, which are missing the oak leaf and acorn festoons, and each with an added second branch by Robert Garrard, 1856, that formed part of the Sneyd Heirlooms which were sold in 1924, passed through the collecion of William Randolph Hearst and are now in the Collection of Colonial Williamsburg (J. Davis, English Silver at Williamsburg, Viginia, 1976, pp. 15-17, cat. no. 2).