WATCH POP

After four years of trouble-free service, my Seiko 200M Diver watch finally had it first failure tonight. I found the second hand had fallen off and was floating around the watch. I presume it is a matter of time for the hour/minute hand to get caught over the second hand.
The Seiko warranty is three years, so it has expired by now. Given that, is it something that I can fix myself? I know how to open the case back, but not sure how I can get the movement out of the case. If I take it to a repair shop, can someone give me an estimate on how much they will charge for the repair?
Needless to say, I am somewhat disappointed. So much for the tough watch image.
...in removing stems and decasing movements, Gordon, it would be wise to have a watchmaker replace the hand (which is a friction fit). It's never a good idea to make your first try at watchmaking on a watch you like. Apart from having the correct tools to perform the tasks, the mishandling of an uncased movement with dial and hands attached is a good way to damage it in some manner (hands and dials are especially susceptible to damage).
Don't run the watch further with the seconds hand floating around the dial. In all likelihood the hour or minute hand will hit it and probably just stop, but may also drag it across the dial causing some damage.
This is not a difficult fix for a competent watchmaker.
Paul.