Wrong bezel, marquee, CPO, AND sideart in the sense that they're repros (all have the "NOA" on them).
PCB is anybody's guess. Only way to tell is the title screen.
Buttons are new, probably a new power supply too.
It's definitely beautiful, but probably the only thing original about it is the cabinet itself (if that).
The difficult thing about red DK's is that if you change, update, or replace anything, you sorta defeat the purpose of having a red DK at all. At least, that's how I see it. The four-board set, the ladder cheat, the different isolation transformer, the original, unbranded artwork, it's a package deal.
A blue can be anything, because blues came out of the factory in a number of configurations, but if if I were going to pay the sort of premium that sellers put on reds, I'd want it to be all (or at least most) original. Otherwise you might as well just paint your blue cab red!
I've never seen machines as good looking as this guy's, but I think the "newness" is what he's selling, not so much authenticity. Which is fine, because somebody out there wants a machine like that.