It's not as rare as you may think; we’ve done close to one hundred of them on the Ruger LCP and Taurus TCP. My husband does the sight mod and I refinish the slide. Refinishing is required due to the machining process on the slide. He uses a front tritium night sight and builds the custom rear sight. He cuts cocking serrations on the front of the rear sight to assist with one finger charging of the weapon. It’s becoming a pretty popular sight mod. Two of the pics I posted are ones a client sent us from his posting on the elsi pea forum.
http://elsiepeaforum.com/forum/index.php?topic=10017.0