I just added up basically the cheapest components you could buy from RG. Some would be better than the BD offerings, some would probably be about equivalent, but the total came to like $450(with shipping), so I honestly can't argue with your plan. At least it gets your bike rolling and you can upgrade components as needed.

I'd just find whichever one on BD that comes with a 1 1/8" stem(should be all but the Kilo TT and variants, and the Premium Brew), a 27.2mm seatpost, and the color of components that you want.

Edit: The Dawes SST AL would probably be the best if your budget allows for it. Plus a brand new aluminum "fixie" frame with a carbon fork would probably be the easier frame components to sell and recoup some of your cost.