Pretty sure these lamp bases are 1940 or after !!Have found none similar but that is not unusual !! To find a similar set we would need to know how someone else has them described !! The mark you see is not a makers mark or factory mark nor an import mark !! It is probably a decorators mark !! Many mfrs paid their artists ( usually women just making extra money) by piecework !! They were paid according to how many of these ceramics they decorated !! Each had their own mark !! Could be anything from initials to symbols or numbers !! These items were tallied each evening and each payday to see how many they would get paid for !! The gold is the last color to be applied so that is the color used for their mark !! These most likely had a sticky label which is long gone !! Most lamps even in the US are not marked at all !! They are nice and different from what you usually find !! Are you going to return them to lamps or just use as figurines ??