Oddly, all the details I can find reference Edgecumbe Hall, not House, but I think it's the same place. Oddly, the listing for this specific gateway doesn't mention the exact name carved on it, but lists it as "GATEWAY ATTACHED TO THORNTON HALL AND EDGECUMBE HALL, RICHMOND HILL".
GPS Coordinates:
51.45744, -2.61098
Location: Queens Road