Hi, just got back from a hunting trip in the West Country!
The ident on your plate is not straight forward. The Mark 4, 14 inch Ransomes mower started manufacture in March 1938 and ended in August 1951, but production stopped during world war 2.Your machine T9714 dates to August 1949. Spare parts for your machine became obsolete on 31st of May 1966.
I hope this information proves helpful to you, However I did notice you asked elsewhere for help, with no one answering your quest, this is the site for honest answers
Andrew Hall
Archivist
The Hall & Duck Trust