Russian NVG
I hope you only want them for night gardening or whale watching.
Please tell me you do not want them for anything related to flying!
If you have a helicopter capable of night flight, which wasn't a cheap investment, you take your life seriously, then spend the correct amount on a product that works. You wouldn't buy a £100 flying helemet or £20 artificial horizon... I hope.
The danger of using half capable peices of equipment like those is the false sense of security you can be lulled into.