I second the screw on sights, the Williams or maybe even a TC might fit. You can 'recontour' the curve underneath, if needed, with some sandpaper wrapped farther up the barrel taper untill you get really close.
Not that you cant dovetail it, but short jigging it up straight and square in a mill it is a touchy job that cant really be corrected once it goes bad, and a poorly done dovetail will always be 'looking back at you'.