FYI, I sold my 17" GTI wheels for €900 on eBay (approximately £800). I paid €1000 for the Interlagos from Germany.
Even though I won't be getting the car until mid-August, I put the advert up anyway, obliously stating clearly that I was taking reservations only and that the wheels wouldn't be available for a few weeks. If anything, this approach actually seemed to attract even greater interest and the wheels had been sold within 4 or 5 days! I think people liked the idea that they knew they would be getting brand new wheels and, perhaps more importantly, brand new tyres.
Based on my experience, I would strongly recommend that you try to presell your wheels in the same way, because even if you only do a couple of hundred miles on them, their value will drop significantly.
Hope this helps