Best bet is to paint it with Duracoat or something similar.
You will basically need to fully strip the gun down, unless you are okay with getting "ghosted" images of the firing controls and such...
You could probably find someone to paint it for you on a more professional level, although getting them to the point of the internet pictured ones is not such an easy task!
I think you can purchase pink furniture (stock/pistol grip/forarm) for Ar15's, but you would need to do some digging on that. Those would be fairly easy to get painted up though (for just black ones), just get a rattle can of good pink spray paint and put a 3-6 light coats of it on.