About the rumour that the Benns came from Canada.Two of my great grandfather's siblings (who lived in Londesborough Ontario) married Benns who came from Montreal Quebec.These Benns may or may not be related to yours.
Seems that your Benns (like my Cravens) headed West.The journey was usually through Minnesota and North Dakota to Manitoba (with many families settling along the way).
William Edgar Craven -born: September 26, 1840 -died: April 19, 1891 -married: February 25, 1873 -wife: Louisa Benn, Montreal Quebec
Charlotte Craven -born: April 29, 1842 -married: June 3, 1873 -husband: Alfred Benn, Montreal Quebec -----children: Ethel Benn
You can check for Benns on the Manitoba Vital Statistics http://vitalstats.gov.mb.ca/Query.phphttp://vitalstats.gov.mb.ca/Query.php Ontario and Montreal Vital Statistics you have to write away for.