The Norfolk jacket was arguably the "casual" coat that re-started the mode of trousers that complemented, but did not match, the jacket. Of course, men's clothing has gone back and forth from matching to complementing since the first dandy invented pantaloons shortly after discovering fire. But we owe the current era to this, the first modern sport coat.
The principal feature of the Norfolk is the shoulder construction that made it easier to raise a gun to bear on a bird. And this same feature is the principal reason we see so few of them today. The action back and half belt make it more complex to sew, which translates to more expensive to make. Which in turn means it won't be found on many retail racks.
Still, a man wearing one won't see himself coming and going. And he can dress it down with moleskins or dress it up with gabardines like the man in the illustration. Because his trousers don't have to match.