A county clerk may at any time more than six years after the entry of final judgment in any action apply to the superior court for an authorizing order and, upon such order being signed and entered, turn such exhibits of possible value over to the sheriff for disposal in accordance with the provisions of chapter 63.40 RCW, and destroy any other exhibits, unopened depositions, and reporters' notes which have theretofore been filed in such cause: PROVIDED, That reporters' notes in criminal cases must be preserved for at least fifteen years: PROVIDED FURTHER, That any exhibits which are deemed to possess historical value may be directed to be delivered by the clerk to libraries or historical societies.