Unknown O4 Class

Photograph of Unknown O4 Class
Loco number: Unknown
Loco name: n/a
Loco class: O4 ?
Wheel arrangement: 2-8-0
Location: Catesby Tunnel
Subject type: Steam locomotive and goods train
Date taken: 1948
From/to: n/a
Notes: Cylinder front plate has rivets around circumference - is this an O4 variant perhaps?
Region: Great Central Railway (GC)
Power classification: Not rated
Designer: Unknown