Whenever a department head desires to fill a vacancy in the classified service, and the Director of Personnel cannot certify eligibles for such vacancy because there is not an appropriate list or because there is not a sufficient number of persons on the appropriate list who are willing to accept appointment, the Director of Personnel shall promptly report this fact to the appointing authority. The appointing authority may then fill the vacancy by making a provisional appointment of any person qualified to perform the duties of the position. A provisional appointee shall hold position only until an appropriate list has been established and the required certification can be made. No provisional appointment shall last more than six months. Provided, that any provisional or emergency employee shall, upon the completion of 60 days' service as such, be entitled to a departmental work evaluation by the department head or his designee. If the said evaluation shows that the work performance of such employee has been fully satisfactory, the department head, with the approval of the Governor, may certify such provisional or emergency employee to the appointing officer for permanent appointment, subject to the provisions of section 527 of this title.