That case is gorgeous!
The center strip is said to be stainless, but being that thick, it could be done with aluminum, brass could look cool for a more steampunk look as well. As for the plate itself, it's likely 1/4in (or metric equivalent) milled out from the underside, if you have seen the underside of a Vortex Filco case (look above the arrow keys)you will
see what I'm referring to. A chunk of stainless milled like that, will probably not be cheap, and regardless of stainless or aluminum, I would leave some internal ribbing for strength.
As for the wood, you won't get that look with Oak, much less Pine, that's Teak wood. Walnut could also give you that sort of appearance. Burlwood would also be cool to use if you want a rich look. The key word here is rich, none of those woods are cheap to acquire. That's $150-$250 worth of wood you're looking at if done in Teak.
If you do it yourself, you could go cheap and do the case for $100, but to really do this right you could easily break $1000.