Tamiya does some race car drivers and pit crews in 1/20 scale. You may be able to modify them. They have racing helmets on that could be modified to look like hleo crew helmets as well. Good luck, not much out there in 1/24 figures, especially military ones.
Gino P. Quintiliani - Field Artillery - The KING of BATTLE!!!
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"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." -- George Orwell