I bought it about 15 years ago, used, with a scope and no rear sight. Need help in identifying the part number of the complete rear sight. Might not make any difference but there's no guarantee that the barrel is original to the frame.
Gun Parts Corp. shows a break-down of all the component parts which doesn't help me.
My 2010 Model 41 barrel has a Millet size dovetail for the rear sight. I have heard there are different sizes depending on the year of manufacture. I bought a new rear sight from Bullseyegear and it fit fine.