If a 10lb hammer won't fix it a 20lb will
I have only drilled out 1 set of SR pins.... However, I have drilled out many similar pins and very small fasteners. The easiest way, IMHO, is to use a drill press and small centerdrill then a small drill to drill off the head then punch it out with a small undersized pin. Once the head is gone you should have little problem. The threaded fasteners need a tad bit different technique.
Just how I do things.
Jeff
After seeing someone here suggest using a pair of flush cutting pliers I haven't used any other method since. I bought a pair at Harbor Freight for like $2.99 and they work like a charm. You can find these at hobby or craft stores in the jewelry making section. I just get the cutters under the washer and snip the scales are apart with no damage what so ever to the scales.
I generally file one end of the pin flat then using a very small drift, punch it out. You need to be careful not to file too far or else you will end up ruining your scales.