Hi Peter,
Well if you are going to buy nearly new that's the way to do it. That's a massive saving on the new price.
Just looking on Auto trader there are plenty of S Types. Some look like they've had a hard life but are very cheap whilst others look like they have hardly ever ventured out of the garage. I think I would probably be avoiding the cheap ones and going for something which has been looked after with good service history and lowish mileage.