Don't forget about John Kaase...
http://www.jonkaaseracingengines.com/
But I still say you should find a local builder. I have about 8-9K in my engine, complete, including fuel injection and supercharger. Yes, I built a lot of it myself...the bolt-together part. All the engine machine work, cnc stuff and such was hired-out. If money is any concern for you at all, I think you can do this far more affordably locally...and develop a support network while you're at it. If I built my engine again and just went single carburetor and naturally aspirated, I could build a 545" NA stroker for under 6K complete I bet.
If money is no concern, then I'd have Kaase build an all aluminum monster, break it in on the dyno, and all...why not.