Japanese relatives - help my search?

My great-grandfather was Takanosuke Oishi (大石) BD. 1885. September 29, born in Shanghai and emigrated to Fukuoka in the 1940s after the war. Takanosuke passed away in 1953 in Fukuoka City. His wife was Shizu Eguchi（江口シヅ), BD. 1903. September 16, born in Nagasaki City. We know the whereabouts of the eldest of Takanosuke and Shizu's children, Judy (Misako), born 1925, who emigrated to the USA and are looking the other 4 children of Takanosuke and Shizu, last seen in Japan in the 1980s when Judy visited her mother and younger siblings.

We are looking to find out what became of:
Michiko Oishi (大石美智子). Born 1927. Last known to be living in Kyoto, in 1983. Husband was Hajime Kosaki.
Shigeru Oishi (茂). Born 1930.
Tatsuo Oishi (辰夫). Born 1935.
Toshio Oishi (大石利雄). Born 1940.

I have Koseki [Kaiseigen Koseki] 009 0524/ 2008 147- & [Kaiseigen Koseki] 114 0351 / 2110 035

Can you help me?