Hugh,
The California Death Index, online, has an entry for a Robert Lewis Rizon, born Aug 5, 1912 in Pennsylvania, died Aug 7, 1989 in San Diego (County), California. There is no entry for him in the Social Security Death Index, just a Robert Michael Rizon, born 1938. Ancestry.com shows him as marrying in 1952 in Palm Beach, and again in 1973 in Las Vegas to Kathylean Oliver M Rizon. The phone has apparently stayed in the name of Robert L Rizon ever since his death.
I would assume this is the person you are interested in. To obtain an obituary (which I could not find on my regular obituary source), I would go to the website for the San Diego Public Library
http://www.sandiego.gov/public-library/ and click on Services and try Ask SDPL or QuestionPoint 24/7 Reference. They can probably find an obituary and email, or snail it to you.
Frank.