Made in 1983.

Here's my gun store examination (when you have no tools and just have to use what you have with you). To check the timing, make sure the gun is empty (then make sure again), then pull the hammer back slowly -- the cylinder latch at the bottom of the frame window should click into each cylinder notch before (even just slightly before) the hammer locks back. Check each chamber.

To check tightness of lock-up, pull the trigger and keep holding it back after the hammer drops. With the trigger still held back, try to wiggle the cylinder side to side. A tiny bit of wiggle is fine. What's too much? Once you have tested a few guns that you know are OK you can easily tell what's too much (too much and you will be shaving lead and spitting it). Test each chamber. The cylinder should never allow you to wiggle it right out of the notch!

The cylinder gap between the cylinder and the forcing cone should not allow the corner of a standard business card to slide in between -- still you should get a bit of daylight on each chamber. Test each.

Make sure the cylinder opens and closes smoothly. Make sure the trigger pull is smooth (once again if you have pulled triggers on several "good" S&Ws, you will know the feel).

Then, look down the sights and see if the barrel is screwed in to straight-up 12 o'clock (occasionaly the factory over or under screws the barrel). If they shoot to point of aim a lot of guys don't mind a slight cant -- but in buying a used gun -- I'd prefer a 12 o'clock barrel.

To check the bore, use a white business card to reflect light up the barrel. If it lacks pitting and the rifling is fairly sharp (albeit sometimes a bit dirty) it's good.

Oh, if it's good, $500 is ballpark.