The commission shall purchase directly from the manufacturer, except under the following conditions:
Foreign brands which are not readily obtainable directly from the manufacturer.
When the commission can conclusively prove that unusual or extraordinary circumstances exist and the required or desired brands can be purchased at substantially lower prices from wholesalers or brokerage firms.
In all instances involving purchases, other than directly from the manufacturer, the commission shall maintain full and complete records clearly reflecting the justification for such purchases. Said records shall include invoices, price lists, comparative prices, bills of lading and a certificate of justification signed by the director of the alcoholic beverage control division, as to the conditions requiring the purchase or purchases. All such records shall be retained for a period of three (3) years.