I bought this years ago and have never shot it. I thought I'd start loading .357 and just never got around to it. Thought I'd sell it and look for another 44mag.
Not sure on what it's worth without an in person inspection, but an early fixed patridge sight would up the value, since most 6" 686s I see from the 1980s seem to have the red ramp or four position adjustable front sights. I have the red ramp on mine but would love a patridge. Not having the "M" upgrade (a/k/a the "L Frame Improvement Program") would drop the value to me as I would count on having to send it back to the factory for the upgrade. I have owned two 686 no dash revolvers and both would tie up the cylinder with some or all magnum loads.
As far as a date, I know of a model 681 with serial number prefix AAP was produced in February/March 1983. Yours would likely be near that time, but nothing is for sure with S&W serial numbers.