Locating their arrival manifest would provide you with a location.
What sort of US documents can you locate on Rosa b. 1905 who was born in "old country"?Was she naturalized citizen? Did she have social security numbers? http://ssdi.rootsweb.comhttp://ssdi.rootsweb.com Her church marriage record should have her place of birth.
You might try locating his church baptismal record. Louis b. 10/2/1909 New Jersey d. 7/1983 Roebling, Burlington, New Jersey
What does the 1930 census say for John and Flora? Na-naturalized, Al-alien or Pa-first paper?