Municipalities of this state under ordinance of the governing body are empowered to acquire by purchase or lease, and to maintain and operate, in cooperation with neighboring municipalities of states bordering this state, the out-of-state property, plant and equipment of privately owned utilities supplying water to the purchasing municipalities from an out-of-state source: PROVIDED, The legislature of the state in which such property, plant, equipment and supply are located, by enabling legislation similar to this, authorizes its municipalities to join in such acquisition, maintenance and operation.