Just a suggestion,... you might be better off trying for a pure black uniform requirement, cause I can't see all that many worth while ppl who would suit the role having full urban marpat uniforms yet seeing as how it's a pretty new camo type.
From the sounds of it you're looking for a smaller squad based senario being that specific.
If so and you realy want it to be authentic looking you'd better start doing your home work on marine tactics and movement procedures, and be prepared to spend alot of time getting it out of whoever shows up.
Throwing a bunch of guys who probably don't know each other or what you want from the scenes together, and telling them to just go at it just won't cut it as anything usefull for any kind of movie.
"Death in the tall grass"