Are you more interested in the Nav lights? Or just the LED docking lights? For both, the housings for each are made in house for each boat manufacturer. If you just want the Nav lights, then here's a site that has a ton of options...
http://www.westmarine.com/navigation-lights
If you just want the docking lights They have a few options there too but nothing like the LED strips on the G or Supra. Like I said, those enclosures are probably all designed and produced in house. Just guessing though.