Also keep an eye out for a GT TDi spoiler as it is pretty much the same (if not exactly the same) as the GTI.
http://www.ebay.co.uk/itm/NEW-Original-VW-OEM-Roof-Spoiler-VW-Golf-5-V-MK5-Limousine-GTI-R32-/130687562693?pt=Motors_Car_Truck_Parts_Accessories&hash=item1e6d95f3c5Just shy of 200 notes, brand new and OEM.Have used this seller before (tuning fanatics) and can fully recommend them.