White LED rear numberplate lights

One of my standard rear numberplate lights isn't working and Audi said that it's not just the bulb but the bulb holder also needs replacing too.

Well I thought I may as well changed the lights to white LEDs while I'm at it.

What parts do I need to do this conversion? Is it just the standard bulb holders but with LED bulbs or is there more to it than that?

Cheers