At Valken Tactical, they've got a MICH 2000 Helmet that comes equipped with rail mounts. This costs US$44.95 and available in Black, Green, and Tan... "Which Helmet do you wear and why? This is our Valken Tactical Airsoft MICH 2000 Helmet with mount & rails.

DETAILS

• Training Style Helmet
• Removable/Adjustable Padding
• Modular Side Rail System
• Metal NVG Shroud for Action Cameras, Night Vision, etc.
• Velcro for Team Patches, Flags, and Accessories
• Comes in tan or green
• Adjustable Chin Strap 
• For airsoft use
• Master Pack: 10"