Cool-looking rifle in the middle photo. What is it? What about those stocks?
Looks like an upgraded verion of the M-16. Could be some "local color" added by an inventive GI.
Looks like a standard M4-type set of stocks, except they're molded in coyote brown. CAVARMS makes a set in just about every color, including DeWalt Yellow and Barbie Pink. The pistolgrip is completely aftermarket, though. Looks like a First SAMCO grip.