Here are a number of Koberstein spelling variants from Russia landing in Baltimore:
Name Arrival Date Estimated Birth Year Gender Port of Departure Last Residence Ship Name
Emil Kaberstein May-13 1895 Male Bremen, Germany Russia Neckar
Abram Kuperstein Jun-11 1906 Male Bremen, Germany Russia Cassel
Aran Kuperstein Sep-03 1885 Male Bremen, Germany Russia Rhein
Chune Kuperstein Jul-04 1878 Male Bremen, Germany Russia Chemnitz
Gissie Kuperstein Jun-11 1903 Female Bremen, Germany Russia Cassel
Itte Kuperstein Jun-11 1900 Female Bremen, Germany Russia Cassel
Itzek Kuperstein Jun-14 1894 Male Bremen, Germany Russia Friedrich Der Grosse
Mendel Kuperstein Oct-05 1884 Male Bremen, Germany Russia Cassel
Sisie Kuperstein Jun-11 1873 Female Bremen, Germany Russia Cassel
Chime Kupperstein Nov-07 1882 Male Bremen, Germany Russia Cassel

Baltimore Passenger Lists 1820-1948
Name Arrival Date Est. Birth Date Gender Occupation Port of Departure Last Residence Ship Name
Aug Koberstein 24 Oct 1888 abt 1847 Male Locksmith Bremen, Germany - Herman
Emilie Koberstein 24 Oct 1888 abt 1842 Female - Bremen, Germany - Herman
Anna Koberstein 24 Oct 1888 abt 1873 Female - Bremen, Germany - Herman
August Koberstein 24 Oct 1888 abt 1877 Male - Bremen, Germany - Herman
Ernst Koberstein 24 Oct 1888 abt 1882 Male - Bremen, Germany - Herman
Gustav Koberstein 19 Apr 1887 abt 1871 Male Merchant Bremen, Germany - Donau
Yata Koberstein 19 Apr 1887 abt 1868 Female - Bremen, Germany - Donau
Carl Koberstein 14 Jul 1893 abt 1870 Male Farmer Bremen, Germany Volkersleier (1) Weimar
Niclaus Koberstein (2) - - Male Shoemaker Bremen, Germany Hirschfeld Helene
Magaretha Koberstein (2) - - Female - Bremen, Germany Hirschfeld Helene
Johan Koberstein (2) - - Male - Bremen, Germany Hirschfeld Helene
Louise Koberstein 21 Dec 1889 abt 1861 Female - Bremen, Germany - Main

(1)  The transcription that Ancestry gave for the Last Residence is Bolkersbred, but I think it looks more like Volkersleier.  In any case this family is from Volkersleier in Bavaria so that is probably correct.  See Volkersleier in southern Germany.

(2) Here is the actual Passenger List index cards for these people.