To be perfectly honest you can't guarantee to find a nice, sensibly priced, rust free car without putting the miles in to see it for real.
I upped my budget when I bought mine 5 years ago and bought from a local specialist that had 3 suitable cars to choose from. I figured that I could have paid less money from a private sale, but all the time spent travelling round, sifting through the tat and not earning whilst doing that, could mean that the cheaper car may well actually be more expensive.
Looking for cars at shows is a very good idea, but even then, don't be afraid to have a rear good poke round for rust. There are a lot of pretty looking cars out there, but whilst many owners of original, solid cars will want to keep them for ever, you need to question why someone would have theirs for sale. There is probably something lurking behind the big bumpers that they don't want to spend the money on.
