I purchased a 90mm light ring from
--->Super Bright LEDs. <--- Make sure you get a diffuser with them if you go with that route. It keeps the contaminants off of the LEDs and, well, diffuses the light. I used a 12 volt wall wart to drive them, which I most likely had laying around from something. 3D printed a switch holder and I was good to go. I believe I used some
---> E6000 <--- to glue the light ring up to the spindle. Very happy with how it turned out.
EDIT: Make sure you get a light ring with an LED driver or purchase one separately.