The officer who oversaw the registration asked the couple for their signatures, which they dedicated to his daughter, Gillian, and his son, Graham.
Ewbank said: “There was fierce competitive bidding online and on the phone for the item. What made this one so special was that it was signed by both Marilyn and her then husband, the writer, Arthur Miller.”
He said the book had been “unusually” signed by the Hollywood star as Marilyn Monroe Miller.
Ewbank said that interest in Monroe was “really high” currently, amid renewed interest in her life and her relationship with Miller.