Update :
I started out wanting a brass bead for my SP101 front sight ; several friends moved me away from that. I came here for advice , steered away from the Gemini gold bead due to cost , almost went with a HiViz - but still had the image of the combination of stainless , walnut and brass in my mind. So ...
I located a substantial brass bead with a threaded post small enough to be threaded into the 1/8" stock blade sight. (The bulkiness of the stock sight turned out to be an advantage...) I scribed the base of the sight blade then removed it and paid a visit to the friendly neighborhood machine shop. The machinist noted that my idea of milling the blade to be flush with the barrel surface was flawed - The sight is shaped in such a way as to extend beyond the milled slot in the top of the barrel fore and aft ; it sits atop the barrel for the purpose of stability. Rather than milling the sight blade to be flush with the barrel and having the base of the bead sit atop the blade base , he intends to leave the blade base stand proud of the barrel surface by a fraction of an inch and recess the bead into the blade , achieving the same height as the original.
My monetary investment in this project will be very small , the machinist being a friend , and the risk is only a stock blade worth about $15. I hope to achieve an attractive and functional one-off , a custom brass replacement for a sight I strongly dislike on a revolver I otherwise like a lot. Photos of the finished product will follow. That should be fun - some will like it , some will probably think it an atrocity. That's what makes the world go 'round and the forum fun , eh?