Such state transportation department or other body designated by law to have charge of the state highways of the state of Missouri shall have the right to maintain and operate such land, mines, quarries, plants, factories or other property to manufacture such road building or road maintenance material, and such transportation department may sell and dispose of the materials and products produced by the operation of such land, mines, quarries, plants, factories or other properties to counties, townships, road districts and other political subdivisions of the state.
§ 226.260, RSMo