As far as I know it has been out of production for some years. Swing the cylinder out and the model number should be stamped inside the area where the crane fits. Pic of my 4 inch model 689 below.
Yes, this is a .357mag revolver, and can also shoot .38 spl rounds. If you use .38spl rounds, which have cases that are slightly shorter than the .357mag cases, you may encounter fouling at the front of the chambers that can then cause the longer .357mag cases to stick and be hard to extract. This is an issue encountered with many .357mag revolvers. I find that a throrough cleaning of the chambers after shooting .38spls keeps this at bay.
My Model 689 has performed well.