Export Publishing Enterprises Ltd published 55 paperback originals in 1949, 1950 and 1951. Taking into account known pseudonyms there are 44 named authors plus two anonymous editors of collections. Only 13 of the 44 have been identified. The remaining 31 authors make their only appearance in an Export book. I can find no other books they wrote or anything about them.
Here are the last three PBOs from the anonymous authors published in January 1951.