Stephen - I'm not aware of anyone that has accurate plans for a block-front chest of drawers for sale specifically. However, you should contact Alan Breed, as it's quite possible that he has built one of these, and more than likely gotten access to completely go over one of the originals. Even if he doesn't have a set of plans to sell you, he might be able to answer specific construction/joinery questions.
I am looking for the person, I believe Jay Stallman, to whom I e-mailed a Google Sketchup file for a Newport Block front that I have been working on within the last week. Two days ago I had a hard disk drive failure, and my backups have not been working due to a new OS, etc. etc., etc.
If you are the personn I sent it two, and you still have it, I would be very grateful if you could e-mail me a copy back.