Although it looks fairly simple, this LED lamp is quite challenging to print. http://birkbinnard.com/blog/a-challenging-print/ is a blog page that provides background and hints for making a good quality print.
The lamp is designed for an LED "puck" light. Battery operated lights are about $4 each; simply do a web search for "LED puck light" to find several sources. This blog page tells where you can get wall powered lights that are brighter and that work very well: http://birkbinnard.com/blog/wall-powered-led-lights/.
This print took just under 36 hours using a layer height of 0.140 mm and a print speed of 100 mm/sec.