I presume the Khmer Rouge guerillas wore the same peasant outfits and Chinese-supplied equipment as the Viet Cong in the 1960's?

Also, I read that the US secretly supplied the Khmer Rouge guerillas during the 1980's in their fight against the Vietnamese occupiers of Cambodia.

Tom,
Yes, they dressed very similar to the VC - black PJ's, AK-47's, Chinese equipment, etc, etc. Although after the Cambodian incursion in 1970 there is much photographic evidence that they were using pilfered weapons of US origin.
They did, however, wear the very distinctive red & white checked scarf around the neck or head. Which I guess would be quite challenging to paint.
Hope this helps, mate.

Joe.

They generally wore a soft military cap probably of Chinese origin and their kramar, or scarf, had a very small checkered pattern and could be red/white or black/white. Cambodians are also generally darker skinned than Vietnamese, especially the peasant farmers that made up the Khymer Rouge.