Make sure your gunsmith is familiar with CZ's. The one I used, through my local gun store, was not familiar with CZ's, and he drove the safety lever out by sheer force, chipped the polycoat and dinged the frame, sheared off the sear spring leg, which nestles into a notch in the safety lever (and decocker) shaft, and lost the pin you are also missing. That's how I know the pin you speak of.