Are you saying you are missing the head bolts? Most blokes will source them from another engine, say from the wreckers. You can also buy new ones from Nissan. Head bolts are special items
9 needed
http://www.courtesyparts.com/oe-nissan/11056h23011 needed for newer blocks (1974 and newer)
http://www.courtesyparts.com/oe-nissan/11057h5700