SAS has low fares from $528 to $544 round trip to several cities in Norway and Sweden for travel from November 1 – March 31. Airports include Oslo, Bergen, Kristiansand, Alesund, Stavanger, Haugesund. Stockholm and Gothenburg, Sweden are also priced low. There is good availability on most dates outside of the holiday travel period of mid-December to early January. Some flights involve connections on United to Chicago or Newark and others involve SAS directly from SFO to Copenhagen or Stockholm for Scandinavian connections.
These flights are searchable on Google Flights for dates and then bookable directly through SAS website.
San Francisco to Norway and Sweden Google Flights filtered for Star Alliance Feb 7-14
SAS San Francisco SFO – Copenhagen CPH – Bergen, Norway BGO