WW2 British MkII Helmet - Free French Forces ?

A British MkII helmet stamped RO Co 1939 with Mk1 liner stamped Helmets Ltd I 1939. The helmet has had a dark green/brown camouflage, slightly textured paint applied. The left hand side has a painted diamond emblem which I believe to be that of the Free French Forces, although faded the colours are clearly visible blue, white and red.

Code: 51805