Buckeye Shooter,
He could be a LRRP. Thats probley a PRC 20 or 25. The Marines for some reason liked the old stuff, PRC 15's And the old WW2 canteen's with the small black plastic top,s, if you notice the Army Grunt in the pic. is carring the newer large o/d cap canteen's. The Army seem's to have got the newer stuff, If you remember the marines were the last to give up there M-14's.
Im not an expert, But i play one on the internet {Stolen]. lboos.