Irish Free State Army

From the 1930s. Vickers mild steel helmets, in the shape of the German M16. Darkish green uniforms. Reddish-brown leggings and boots. British gasmasks. Blackened webbing equipment, and SMLE rifles.

Two different types of helmet?

Just the one I think. Where's the second.

Below is the full dress uniform of a member of the Medical Corps.
Officers were allowed this attractive uniform, with styles for mounted and dismounted corps, and then in individual corps colours.

First two guys on the right. One you can see the angle or corner in the rim where it flares to go around the back. The man next to him seems to be smooth without an angle. Trick of perspective, or slightly different models?