Are any of his direct descendants still living? If so, have them write to the archives for his service records. I think it is located in St. Louis. I'm doing this from memory. I have my father's and my father in law's records from WWII. They will also send you a listing of his commendations and medals along with his medals for free to the living descendant. Receiving the medals might take awhile, from 6 months to a year. If once the family member receives the records, the medals and commendations can be purchased online.

You might want to try and get the records yourself, but you will have to state your relationship and send or fax a picture ID.

Here is 1 webpage. Not sure how this works.
http://www.recordsbase.com/?act=military&fc=93&fck=us-navy&utm_source=adw&utm_medium=cpc&utm_campaign=military&creativeid=g10176108824&utm_term=US%20navy%20WWII%20records&group=adw-united-states-navy&network=s&site=&ran=797150483102521511&target=&aceid=&asl=[name]&match=b&gclid=CNWYq_XLpKkCFQEHbAodL2bVsw

And here is another
http://www.public.navy.mil/bupers-npc/career/RecordsManagement/Pages/default.aspx

Hope this works for you.
Linda