I'd contact the Mason County Gen. Soc., PO Box 1535, Shelton, WA 98544-1535. Hopefully they have the City/County Directories for 1911 and other info about him. They might also have the WA Death Index (microfilm) and can look up his death date. Once you get his death date, you can check for an obituary or they do that too.
If that doesn't work out, there is a Mason County volunteer on Random Acts Genealogical Kindness, www.raogk.org, choose Washington, choose Mason Co. Successful Hunting!