Notwithstanding the provisions of Kan. Stat. Ann. § 74-4902, 74-4911, and 74-4913 and subsection (2) of Kan. Stat. Ann. §§ 74-4935 to the contrary, an employee who was first employed in the public schools of Kansas in the school year 1957-58, who became a member of the Kansas public employees retirement system on January 1, 1971, who forfeited all service credit under such system on March 6, 1974, by reason of termination and withdrawal of contributions, who was again employed by a participating employer on August 23, 1979, and who was born May 2, 1919, shall be a member of the Kansas public employees retirement system on the effective date of this act. Such member may purchase participating service credit under such system for the period from August 23, 1979, to the date of membership under the provisions of this section by means of a lump-sum payment equivalent to four percent (4%) of the compensation paid to such member for personal services during such period, except that such lump-sum payment must be made within six months after the effective date of this act.