The US Marines uniform in desert consists of three colors. The base of the uniform is light tan, with digital blots of medium tan and medium brown. I'd go with a light brown for a combat troop since the sun and sand bleach the uniform. The knees and elbows are practically beige after about two months.
The IBA, or vest, needs to be a NATO brown, NO CAMO. Weather a bit lighter since they too bleach in the sun. Vest shells are made of Cordura Nylon and do not bleach or fade as fast as the pants, something to note.
Boots need to be light to medium olive-drab. The Marines got a contract for OD Boots, blends in better than the Air Force Sage Green or the Army Tan.
Most pouches and misc. gear will be NATO brown no camo.
Anything else you want to know? Good luck on your figures.
- Hiroshi