The coins are offered for $5.95 each. The Mint has placed an order limit of 5 units per household. The Mint’s product page is available here.
This is part of the array of individual ordering options that the Mint has been providing for the Presidential Dollar series. The individual coin is already available as part of the 2008 Presidential Dollar Proof Set priced at $14.95 for all four coins. There is no ordering limit on the sets.