We claim the ornamental design for a portion of a Nordic ski binding, as shown and described.
FIG. 1 is a top, first side perspective view of a portion of a Nordic ski binding;
FIG. 2 is a top, second side perspective view of the portion of the Nordic ski binding of FIG. 1;
FIG. 3 is a top view of the portion of the Nordic ski binding of FIG. 1; and,
FIG. 4 is a side view of the portion of the Nordic ski binding of FIG. 1.
The broken (dashed) lines shown in FIGS. 1 through 4 are included for the purpose of illustrating environmental elements only and form no part of the claimed design.