Case, dial, bezel etc. seem fine. If my memory serves me right that A in stainless was changed from flat to the design you can see on your watch around the late 70s. I don't know when they changed from "Registered Design" to "Original Rolex Design" though. I always thought that this was an early 80s thing, so your 6 million serial seems fine. I'd insist on a movement shot, no way of telling if that one is gen without having a look at it. I doubt that it isn't though since everything else seems to be original.
Edit: I don't think the hands are service replacements, lume seems to match the dial plots. Crown is an early 703. Gen 80s Daytona imo. Don't overpay, apart from everything you read on the net, there are plenty of these around.