Section 7A. The attorney general shall enforce compliance with the provisions of this chapter in accordance with section 4 to 8, inclusive, of chapter 93A. Any retail dealer shall have the right to damages as provided in sections 9 and 10 of said chapter 93A. A final judgment, order or decree rendered against a person in any civil, criminal, or administrative proceeding under the United States Anti-Trust Laws, under the Federal Trade Commission Act, under chapter 93A or under this chapter shall be regarded as prima facie evidence against such person subject to the conditions set forth in the United States Anti-Trust Laws, (15 U.S.C. 16).