$1000-$1200 IMO. May be a little more. You'll need to find a buyer who is only interested in collecting, and not shooting. So, you'll have a smaller market, but one that is more ready to pay asking price if it truly is perfectly in original unfired condition as from the factory. As opposed to guys looking for one that has been shot, so that they can shoot it, who are probably looking to find something in range of fired conditions and prices.
As someone mentioned, there are no useful comparable sales on the common exchanges for NIB examples, so it really is going to be whatever collectors market will bear, and 10xx guns have been trending down slightly since a peak in 2011-2012, but the interest in new is still there.