Here is a lot of 6 issues of National Lampoon magazine from 1979, listed with cover subject and condition issues. These are in Very Good Plus to Excellent condition with no markings inside or outside.
February, Vol. 2 No. 7, Heterosexuality (Mara McAfee), address label scar
April, Vol. 2 No. 9, April Fool (Lou Glanzman), address labels
May, Vol. 2 No. 10, International Communism and Terrrorism Issue (Ray Kursar), address labels
October, Vol. 2 No. 15, Comedy (Marvin Mattelson), address label
November, Vol. 2 No. 16, Love Issue (Mara McAfee), address label
December, Vol. 2 No. 17, Success Issue (Al Murwaski), address label scar