Wooden panel (rectangular) (Royston SG8)

I'm looking for a piece of wood, e.g. a panel from the side of a wardrobe, likely pine (other wood ok, but not chipboard or fibreboard) at least 148 x 60cm, approx 1/2" (1.3-1.5cm) thick. Some scratches or marks are ok but needs to be in reasonable condition. I can collect a few bits and dispose of the rest if necessary.