Ole Knudsen fra Leikanger

I am trying to help a friend trace his Grandmother. Here is what we know: Ole Knudsen married Catherine (or Kathrine) Andersdatter, May 5 1852 in Leikanger. Children: Knud B. 25/03/1853; Britha B.14/10/1855; Anne4 b. 14/03/1858: Marthe b. 19/18/1860; Katrine b. 09/10/1864; Anders B. 16/11/1867. Film 0123141 Census Norde Bergehus 1865 (film HF 112 books 315-318 Hougens Stolediftrift Lekangers) Sogn Lekandgers Broeftegield 31 DEC 1865 Ole Knudsen aage 44 Husfasrer Hors und mar jon Kathrine Andersdatter age 40 huskone Knudt Olsen age 13 son Britha olsdatter 11 dau Anne Olsddatter 8 dau Marthe Olsdatter 6 dau Kathrine Olsdatter 1 dau Now it gets complicated. The family, less Knut (m Gunhild Iversdtr Nov 12, 1872) and Anders (apparently died prior to 1865 census) migrated to America. Date unknown, port of departure unknown, port of arrival unknown. Ole Knudsen died enroute. The mother and 4 little orphans somehow arrive at and settle in Texas. The children were adopted by others. Our person of interest is daughter, Kathrine. New York arrivals yield nothing. Ancestory.com census records yield nothing. Can any information be found in Norway records about emmigration permits, pasenger lists, etc that might help?