While this isn't exactly a high-end phone, I can tell you that from my experience in speccing/architecting a few high-end phone, the screen is _by far_ the most expensive component in a modern high-end phone.
Typically, the screen runs anywhere from $50 to $100
The camera: $10 -> $40 (depending on spec, of course)
The SoC: $15
Other parts that are in a phone that are expensive, but aren't thought of as often:
The PAs for the RF parts
The touch-screen
The five or so custom flex-cables
The flash LED and driver