I would go for the idea posted by Richard and Brian above, that of a dry-brushing technique. A single color straight from the bottle will never give you that appearance. I see a light yellow-greenish tan base, allowed to dry, covered with a thin flat gray, either dry-brushed (acrylic), or flowed on thinly (enamel) and dabbed back lightly with a paper towel until the look is achieved. I find it helps when re-creating something in scale like this, it helps to squint at the surface of your reference to filter out the distraction of thinking too much about WHAT it is, and focus on how it APPEARS. ( Lesson from my painting professor! ) Military hobby paints would be where I would start my search. Experiment first on scrap or even card stock, and show us what you get!