I am not sure about LED's But those lights used for growing indoor gardens should be the closest thing to sunlight.
I don't know where to get the lights, but there are ads run all the time on TV for the gardens, so they probably sell the bulbs too.
Light therapy is a proposed treatment for seasonal affective disorder. It is also claimed "to help with some cases" of major depression. Most of the commercial units available are blue leds..
Actually it looks like they're the same prodect LOL
EDIT: I was actually checking these out now and many of their floorstanding and desk/task lamps are upwards of 96 CRI! For $49 you can get a 14W clip-on desk lamp with 800 lumens and a CRI of 94. I might have to get one of these!
The name of the disorder is Seasonal Affective Disorder or SAD for short.
Most pharmacies sell special full spectrum lights for that.
Most are special full spectrum CFLs $35-$50 but LEDs ~$200 are available.