Every contract, combination, or conspiracy, providing for the establishment or maintenance of minimum prices in the sale of any commodity to the State or any municipality or agency thereof, between manufacturers, producers, wholesalers, factors, retailers, or persons, firms, or corporations in competition with each other is hereby declared illegal. A person who makes such a contract or engages in such a combination or conspiracy shall be fined not more than $5,000.00 or be imprisoned not more than one year, or both. (1963, No. 149.)