My guess is that mechanical spares are reasonably easy to get (the BMC B Series engine for one thing was shared across a large range of cars and in use for many years) but body spares would be like hen's teeth so, if you're interested, check it out thoroughly for rust. I'm just going off my memory here, but I'm pretty sure that the A40 Devon, Dorset and Somerset had a separate chassis, unlike their replacements. At first sight it looks in pretty good condition, but after zooming into the photographs, I think the sills might have a fair bit of bodyfiller in them - I could be wrong, but the surface looks rather uneven to me and, as it has been very recently resprayed (look at the tell-tale mark on the front tyre on the driver's side), so who knows what's hiding under the fresh paint.