Louis Larson - Østby

Hi there, I am attempting to trace our roots and hopefully even find possible family photos if they exist. I have done as much of our family tree on ancestry.ca as I can without upping my subscription. The one line of our family that I seem to run out quickly is my great great grandfather Louis Larson that we believe (was formerly of the Østby family/Farmstead?) who immigrated from Norway around 1893 I believe and ended up residing in Minnesota or Wisconsin Mattsson Østby is the only lead I have for his father The Other dates I have: Possible birthdate August 4 1867 Bergen Hordaland Norway Possible death date July 6 1941 Thief River Falls, Pennington Minnesota Marriage date was August 12, 1893 in Grand Forks North Dakota I do know that surnames and given names were changed when moving to America for a lot of people so I’m hoping the Østby name helps. Thank you in advance for any help. Shayla