I'd follow Flor's plan if I were you and insist on DIYing it.
To do the radius, you will have to make a template, be good with a router and saber saw, knowlegeble in fixtures and wood, have time and be lucky.
The way that I do it involves much of the same except that I have a bandsaw and a shaper. Luck still factors in.
This is why I suggested a local carpenter. The first way might take me 2 hrs., the second, less than 1 hr. Don't forget that the guy has to cover his travel time and overhead. If I were coming in for this job only, no finish, no nuttin, I would charge around $250.00.