I take it then that Beryl married 1950 Apr-May-Jun in Croydon.
Secondly, you are looking for someone who may still be alive, and despite her being your birth mother, it may need some sensitivity that cannot easily be conveyed in a forum. I personally do not know how to search for the living but I wish you well in your quest.
I have been looking on Ancestry.co.uk phone books for 1951 an this places a J. C. Carr at 26, Lismore Road, Croydon. Its a long shot but may help.
I would seek a professional investigator to help you if you have the finances to.