TOKYO — The World War II homefront drama “Post Card” by 99-year-old helmer Kaneto Shindo has been selected as Japan’s entry for the best foreign-language film Oscar.Shindo’s pic, which he has said is his last in a six-decade career, was picked from a shortlist of 22 candidates. Starring Etsushi Toyokawa and Shinobu Otake, it is based on his own war experience as one of six survivors from a unit of 100 men. Opening in Japan on Aug. 22 on 20 screens, “Post Card” has been packing in auds, with its cume to date topping 1 billion yen ($13 million). Born in 1912 in Hiroshima, Shindo bowed as a scripter in 1940 and as a helmer in 1951. Among his best known pics abroad are “Children of Hiroshima” (1952), “The Naked Island” (1960) and “Onibaba” (1964).