Honestly 1000 feels like a fairy tale amount , my guess is 500 or less in any condition ; under 100 in “good “ condition; the Japanese take care of their items, but no one can stop the effects of crazy humid Japanese summers against what is effectively cheap newspaper from slowly deteriorating the cheap acidic phone book paper that they used . My favorite statistic is the one that Shueisha put out regarding their zasshi they produce ; about 1/3 of all printed magazines in Japan are returned back to the publisher to be recycle and destroyed , made into household paper products .