Based on the tank size, the price vary!
I am going to replace (removed) the OEM topfin hood lights, and going to get some USB LED Stripe Lights 5050 RGB, ebay has lots of them, amazon should be fine too. Depends on your choice of brightness, my topfin OEM LEDs are white and so bright that my fish can be blind!! Hehehhee.
Lots of DIY videos in YT for LED strips bif you don't like much brighter lights in the tank, it would be total 35 max but worth the RGB options, and mild light on fish!