This is why I love Banana Republic: they have the most wonderful search capabilities! If you still have the receipt and have the style number then you can call them and have them do a nationwide search to see if any store has it. If they find it you can do a charge-send for less than $10 and get it back. If they dont have it, you can find an outlet and have them do the same thing. The BR 1-800 number does not have access to the Outlet inventory but the Outlet stores have their own system.
This is why BR gets more of my money than almost any store out there. Very few stores seem to be able to match their ability to do this. Even though it was last season, don't give up hope! It is at least a phone call to see if it can be found.
Btw, even if you don't have the style number, the BR 1-800 number people are so helpful if you describe it and the season (winter '08) they will likely be able to find it for you. I"ve had many 'ones that got away and then got found successfully' stories with BR! They rock!