I got the wireless camera system from a place called China Vasion for less than $30. It doesn't have the greatest range or quality in the world but its tiny and the price was right. To mount it I just popped into into place on one of the 'tactical' side rails of the gun. These rails would normally hold various nerf accessories.
I got the laser pointer from a local pest control place as a free gift type thing. I was having a heck of a time trying to mount it and I'm pretty displeased with the final result, even though it works reliably. I simply cable tied a mini servo to push down on the laser button. The laser has a magnet built into the base of it, so I just glued another magnet to the front of the gun to mount them together. I will have to come up with an improved mounting method for the next version.