Expect to pay at least a grand (GBP) (for a knocked-about one), and up to 1,500 (for a good one) for a S/H Lowden - you won't get one for the £500-600 someone quoted earlier. They are top-quality hand-built instruments and, as with all things, you get what you pay for.

If you decide you want one, I know where there's a nice O25 that the owner would let go to a good home for the right money!
S:0)