I've cut hundereds of dovetails by hand with a hacksaw and file. I now have a little mill but I find I can cut a single dovetail faster by hand than by setting up the mill. Your biggest problem will be to find a suitable front sight, not many are low enough or can be cut down low enough.
Here is the barrel of a Remington style .36 caliber I cut down for a friend. It is 4 7/8" with hand cut dovetails for the front sight and loading lever catch. I used a drill press to deepen the hole in the loading lever before cutting it off, all else was hacksaw and file work. The sight as pictured is MUCH too tall and will have to be filed down to bring it to zero.
