Back in the day, going directly to Belt Mountain for the pins was the thing to do. Looks like you can find them elsewhere.
http://www.midwayusa.com/product/827630/...stainless-steelAs Rib noted, the heavier springs can help, but upgrading to a set screw style that will fit the cylinder more snugly as well, is a very inexpensive way to correct and make the gun purtier......
Craig