The photographer was around Petts Wood and Orpington this particular day, this looks like 34035 but this was a West Country engine.

Robert Waterman says "I think this south of Polhill Tunnel north of Dunton Green/Sevenoaks on a Charing X - Folkestone - Dover - Ramsgate service. 34035 was on the Eastern Section at this time when the experimental smoke deflector arrangement was fitted, although I cannot find any evidence that it was officially allocated there. Although Exmouth Junction allocated, it definitely was operating on the Eastern Section at this time. "

And Brian Gregory confirms "I saw her three times at Folkestone during June 1960 and she still carried the Friary Shed Plate. She was seen each time on Commuter Trains. "

Further lan Goodwin says "I saw the loco on the South Eastern too, but this is an up service, taken from the bridge at the end of Telston Lane, just north of Dunton Green. Bricklayers Arms diagram 81 seen here, started with the 09.40 Margate to Charing Cross".