I have a Gen 3 Intevac Nitemate Nav 3 night vision monocular for sale. It is a great unit. The one I have works great, good resolution, it has an IR illuminator. It uses a Litton tube (not the desired tube for a scope application because they don't handle the recoil as well as the ITT tubes do). I am pretty sure it can be mounted on a helmet and I probably have the helmet mounting brackets (almost positive I do). I'm looking to get $2500 for it with an operators manual and all the accessories I can find. Here is a pic