Post war Parahelmet flash

[pluto]

HI everyone , I recently acquired this post war parahelmet with the intention of restoring it for a friend, whil trying to remove the steel grey paint , I came across this flash , I tried to look it up on the net , but couldnt find any info. Does anyone of you experts know what it means? Whether its a regimental flash or not ? Also could it be from WW2, as the helmet was then painted over with a different color ?
Thanks Joe

[kradman]

Looks like a number 63 to me

[pluto]

Yes it looks like a number 63 but if you look closely ,the background is a diamond shaped lighter green color,the diamond measures 7cm across