There is a boxed one in sales atm for £200, but I would guess it will be there for a very long time. Rickenbacker on here spent literally years trying to sell his boxed one, complete with original scope mount and scope for £115, and I have no idea what it actually went for. I would pay up to £80 for a good one depending on condition, but as I use them rather than collect, the box wouldn't add interest or value to me.
Hope that helps.