"So a 4-6 million Springfield with a parked finish, mixed parts, great bore, and walnut stock would fit the bill. Is this all I would need to ask the CMPfor? What more would I ask for? How specific do I need to be?"
As I mentioned, it's a crap shoot!! What you ask for and get in what you describe is like the thing you learn in kindergarten, you start the story and by the time it comes back to you it's changed. Be very SPECIFIC and detailed. Most people aren't. Also, pencil through the cost of buying a SPECIAL and see what the CMP sells both a stock and barrel for, and the cost of installing them plus reparking the full rifle with "new" parts!!. Subtract that from a SPECIAL's price to come up with a ball park number.
FROM THE CMP WEBSITE:
M1Garand, Springfield Special
Due to heavy demand ,please allow 180 days for delivery.
M1 Garand Springfield Armory receiver. New production stock and handguard set with CMP cartouche, a new production barrel and new leather sling. Receiver and most other parts are refinished USGI, but some parts may be new manufacture