Apple has made it almost impossible to compete at the prices they've set at the level of quality the iPad represents.
I totally agree, nobody can lock down all of the supply of a given part in some absolutely necessary, but short supplied, channel better than Apple. It's really one of their most amazing business strategies.
If it were that simple, somebody would have already done it.
I think this article is pretty spot on—Apple has made it almost impossible to compete at the prices they've set at the level of quality the iPad represents. Maybe you can get to the iPad pricing, but you'll have to cut corners and it just won't feel like that solid slab of aluminum.