The scuffs will definitely detract some from the value...do you still have the box?
Re-read the thread and looked at my original grille and remembered the ones I got (GM licensed reproductions) were like the one you're showing w/out the bars going to the end. They were going for 7-800 2 yrs ago New in the GM box on ebay...recently the only ones i've seen sell have been 500-550....
Is it oxidized or just dusty? If oxidized (dulling) I'd say 350-400 with the scuffs taken into consideration...
If it cleans up and the scuffs are minor...400-450
If you find the box...450-500...
assuming you're including the inner....but all that's my humble opinion
