(1) The parties if they so intend can conclude a contract for sale even though the price is not settled. In such a case the price is a reasonable price at the time for delivery if (a) nothing is said as to price; or (b) the price is left to be agreed by the parties and they fail to agree; or (c) the price is to be fixed in terms of some agreed market or other standard as set or recorded by a third person or agency and it is not so set or recorded. (2) A price to be fixed by the seller or by the buyer