I've been a fan of WL Toys for many years, and have three helicopters from them, including one that carries a 720/1080P video camera.
Now, while I've not tried it for airsoft, it occurs to me that this camera, with a little bit of homecrafting, could be adapted to fit a picatinny rail or helmet for airsoft play. As well, being for RC, it's very light, and very compact. Pretty sturdy too, but if it were spanked during a game, at least you'd not be out so much coin.
One example, this
eBay auction for a WL Toys camera, the same as mine, would surely work for those of us who can't afford much, or maybe can, but want multiple camera options.
See if this might be good for your own setup.