You can find listings for a GoPro Helmet Hero on Amazon and eBay, and you can buy newer versions of similar products at GoPro's official website. To get the original Helmet Hero, Amazon and eBay listings are the most reliable method.
The GoPro Helmet Hero was originally listed for sale in 2010, and has been replaced with newer models. Those looking to get the original GoPro Helmet Hero with all of its components can find it by searching on Amazon or eBay listings. However, you can also use the official GoPro website to find newer versions of their cameras as well as helmet mounts in order to get a similar product.