Looking at the profile pics, the top plate looks slightly small for the back plate. The ribs, in places, look to be angled inwards to meet a smaller top plate: but this is purely conjecture based on the photos. It could be that the top and back are from two entirely separate violins brought together to form a composite Amati. As to the question of 'why is the violin unrestored?'. A cynical answer would be: dimensional and form discrepancies between front and back plates would not be immediately apparent in this unrestored state... I hasten to add that I am not implying anything underhand by the auctioneer, quite the opposite, the description states 'all principal parts present' as opposed to 'all original parts present'.