The Squadron book U.S. Tank Destroyers in Action" has a few good shots of Serbian vehicles. There is a Serbian M18 in the colored plates in the middle of the book. It has a green base color with what looks like red brown pattern sprayed over the basecoat. My best description of this pattern is a squiggly line. The few black and white photos don't show markings although I have seen what can best be described as a crest on the glacis plate of the M18.
http://milita1.0catch.com/benkovac/benkovac.html#
www.corbis.com Do a search for serbian, yugoslavian, bosnia etc. You should come up with something.
HTH
Erik
"Don't fruit the beer."
Newest model buys:
More than I care to think about. It's time for a support group.