Joe:
I am a bit of a drive (Raleigh), but I have a few boards left over from this project http://www.ncwoodworker.net/forums/showthread.php?t=37048&highlight=heartwood
I'd be happy to seel you some (cheaper than my cost). It is nominally 8/4, although I can't tell you exactly what the thickness is now (planed) without measuring it.
I bought this batch from the place in Pittsboro that I can never remember the name of - Dave Thurber is one of names I can recall. A quick google search led me to this: http://heartwoodpine.com
I 'heartily' recommend them as a supplier. Pittsboro is also a bit of a drive for you.
Sorry, don't know anyone closer, although I thought Anchor Hardwoods (think that is their name) in Wilmington carried some of this material (at least their former store in Raleigh did, I think). Have you checked there?