If you are looking for a bargain, clones can be a pretty good deal. They aren't the real thing, but they are close, and a lot cheaper. For example, I got a Tempest GTO clone for $3k. I've seen real GTOs in the same or worse condition as mine for up to $7,500. Of course miles play a big part in the price, but if you are going to rebuild the engine/tranny miles don't mean too much. And make sure you look at everything on the car when you inspect it. lift the carpets if you can, crawl under the car, start it up, etc. IMO, if that Duster you are talking about is decent, get it, and invest in a 383 (or bigger) engine block.