A Dean Forest Railway Preservation Society chartered excursion on 6th October 1973 to Long Marston, Quainton and Didcot. The formation comprised 3-car set No. 502 (DMSL W50693, TSLRB W59299 and DMBC W50738).

References:
Dean Forester Comes to Quainton - Reg and Janice Uphill - Quainton News No. 18 - December 1973