A. Any person injured by any violation, or who will be injured from any threatened violation of the Price Discrimination Act may maintain an action in the district court to enjoin the violation or threatened violation. If a violation or threatened violation is established, the court shall enjoin it and the plaintiff may recover threefold, the amount of damages sustained, costs of suit and a reasonable attorney fee.
B. Any person injured by any violation of the Price Discrimination Act may maintain an action in the district court for damages alone and the measure of damages is the same as that prescribed in Subsection A of this section.
C. In any action under this section, upon proof that he has been unlawfully discriminated against by the defendant, the plaintiff shall be presumed to have sustained damages equal to the monetary amount or equivalent of the unlawful discrimination and in addition, he may establish further damages sustained as a result of the discrimination.
D. Where a defendant's trade or industry has an established cost survey for the localities in which the offense was committed, it is competent evidence to prove the costs of the defendant in an action under the Price Discrimination Act.