Hi There,
I have been looking in to this too, as far as I can tell there are around 3 different options aside from the original grill...
You can, as all have suggested go for the Sport Grill - which does look really - good, or go for the Limited Edition two-Bar type grille, which I think would go great on a Black car or go for the Altezza Grill, which is fairly steep and quite Americana aka very Shiney/Shiney lol! -
Hope this helps...
Also - there is the cheaper grills that are available on E-Bay.com - but these are plasticy and seem quite naff build quality...