In this pic, it looks like the guys are wearing uniforms from different armies.
Both are wearing US helmets. The one on the left looks like he is wearing something patterned on British battle dress, but it looks too dark. The one on the right looks like he has more of a US cut to his clothing, but is equally dark.
I have no idea about the weapons, other than they look to be rifles, which doesn't tell you much more than you already knew.
There are posters here that know much more about this than I do, maybe they can tell you more.
http://greatsave9.smugmug.com/photos/191374704-O-2.jpg