You won't find much in 1/32. You can use 1/35 figures with the 1/32 Revell Huey with no issues. I have done it many times and the scale difference is not really noticable.
Here are some options, depending on how "modern" you are looking for. Hueys are no longer in use by the US Army, except for a few left at test centers and a few other places.
Gino P. Quintiliani - Field Artillery - The KING of BATTLE!!!
Check out my Gallery: https://app.photobucket.com/u/HeavyArty
"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." -- George Orwell