That would fit a CXA-3070 led, preferably a flood version.
You need to give more information, like what diameter, how many degrees of flood, smooth or not, etc…
Or you can search for one yourself, just make sure the bottom hole fits the 26mm diameter of your LED or whatever it is: http://www.digikey.ca/products/en/optoelectronics/optics-reflectors/122
The hole should be around 24,5-25mm it is possible to make it biger afterwards, if there is enough flat surface, and the angle of the led is 115°, which is more than enough, so the reflector should be of similar angle.
The whole led is 27,35mm, so if i want to have the wires within the reflector somehow, it must be more than 30mm at the base.
I think the reflector angle should be a lot less than the LED angle, else there is no reason to have a reflector! 
Usually, a narrow band would be something like 15° or less, and up to 60° for wide angle.
Yea you are right, i thought i’d need a reflector 
now i just need a heatsink, capable of dispersing 100w of heat.
CPU heatsink with fan, or
