I'll save ya fom the comments of "use the search button". You can get the OEM lights that fit where the plastic pieces are but your going to have to pony up at the dealer to have them turn that function on. I vaguely remember the lights being about $130. If you want to get the same result at a lower price.....get some generic under the rail lights from Amazon or Ebay. Now if you want them to turn on with your cargo light, you can find the trigger wire on the drivers side sill plate and tap into that. White wire with tan tracer. You can also just run a 12v power line to your fuse box with an add a fuse and then put a toggle switch inside the bed to turn on at your will.
Please, please, please heed my warning as I'm extremely knowledgeable with vehicle electronics.
The LED lights don't take alot of power for them to work, so make sure that if you do mount LED lights run a 5 amp fuse. I have seen where folks tap LED lights into an existing source, get a short, melt the wire and start a fire cos the fuse source they tapped into was 15/20/25 amp and it wasn't enuff to trip the fuse.