Ugh, more and more retailers are pulling "final sale" now! I normally only buy final sale items if I have had a chance to try them on in the store and am fairly confident about the fit. Of course J crew fits are all over the place so it's kind of hit or miss. If you call their customer service, they will give you measurements which helps. But I hear you on the prices - they'll mostly likely do a 20 or 30% final sale soon.
You *can* return a final sale item ordered online if you say it's a gift. They'll give you store credit for the lowest selling price.