Do you have dates? When was she born? When did she move to Sun City? Who was her husband?
There was a Laura Bean, b 29 Dec 1891, d Nov 1976 in Sun City, according to the SSDI.
There was a Ruth L. Bean, b 17 May 1912, d 1 Dec 2007 in Sun City. The SSN was issued in Massachusetts.
Neither of these have death certificates available through the Health Services website, as the dates are too new. If you need to, you could request same through AZ Health Svcs in Phoenix.