The figures in the set are wearing 3-color DCUs. The main color is sand, with larger khaki-green blotches, and brown shadow squiggles around them. Their IBA vests should be either woodland camo or a sandy-tan color called Coyote Brown. For the Khaki-green, Testors MM Radome Tan is close, I mix my own though. The sand and brown are just that; sand and brown, nothing special. For Coyote Brown, MM Field Drab is pretty close.
Check out
this article for more tips and color recommendations for DCUs and Woodland BDUs