you will need to access the power store database directly and run the following sql commands to recreate them:
INSERT INTO `ps4_contents` (`ContentID`,`ContentGroup`,`ContentRefID`,`ContentValue`,`ContentDate`,`ContentUserID`,`ContentPageName`,`ContentPageSetParentID`,`ContentPageSetOrder`,`ContentType`,`ContentParentGroup`) VALUES
(8,'Custom Pages','Content','<h2>Using the Custom Pages feature</h2><p>The Custom Pages feature allows you to change the pages and menu items that are listed in the navigation.  Any new pages that you create based on the \'Custom Pages\' template in the Content column will automatically be added to your navigation menu.</p><ol><li>From the Content column, hover over the Custom Pages option and press the green (+) icon to create a new page based on that template.</li><li>Enter a name for that page (this is what will be listed in the navigation.</li><li>Now that the page has been inserted, you can edit the Header and the Content to say what you would like.</li></ol>','2009-11-19 14:33:24',0,NULL,8,NULL,'WYG','Custom Menu');
INSERT INTO `ps4_contents` (`ContentID`,`ContentGroup`,`ContentRefID`,`ContentValue`,`ContentDate`,`ContentUserID`,`ContentPageName`,`ContentPageSetParentID`,`ContentPageSetOrder`,`ContentType`,`ContentParentGroup`) VALUES
(9,'Custom Pages','Header','Your page header','2009-11-19 14:33:24',0,NULL,9,NULL,'TXT','Custom Menu');
INSERT INTO `ps4_contents` (`ContentID`,`ContentGroup`,`ContentRefID`,`ContentValue`,`ContentDate`,`ContentUserID`,`ContentPageName`,`ContentPageSetParentID`,`ContentPageSetOrder`,`ContentType`,`ContentParentGroup`) VALUES ('111', 'Custom Pages', 'meta-title', 'Page - [Site Name]', '2010-09-27 13:47:34', '0', '', '111', null, 'WYG', '0');
INSERT INTO `ps4_contents` (`ContentID`,`ContentGroup`,`ContentRefID`,`ContentValue`,`ContentDate`,`ContentUserID`,`ContentPageName`,`ContentPageSetParentID`,`ContentPageSetOrder`,`ContentType`,`ContentParentGroup`) VALUES ('114', 'Custom Pages', 'meta-keywords', '', '2010-09-27 13:47:43', '0', '', '114', null, 'WYG', '0');
INSERT INTO `ps4_contents` (`ContentID`,`ContentGroup`,`ContentRefID`,`ContentValue`,`ContentDate`,`ContentUserID`,`ContentPageName`,`ContentPageSetParentID`,`ContentPageSetOrder`,`ContentType`,`ContentParentGroup`) VALUES ('117', 'Custom Pages', 'meta-description', '', '2010-09-27 13:47:50', '0', '', '117', null, 'WYG', '0');