The ornamental design for a handle unit for basket, as shown and described.
FIG. 1 is a perspective view of a handle unit for basket showing the handles in a raised position;
FIG. 2 is a top plan view of FIG. 1;
FIG. 3 is a bottom plan view of FIG. 1;
FIG. 4 is a left end elevational view of FIG. 1;
FIG. 5 is a right end elevational view of FIG. 1;
FIG. 6 is a front elevational view of FIG. 1;
FIG. 7 is a rear elevational view of FIG. 1;
FIG. 8 is a top plan view with the handles shown in a lowered position;
FIG. 9 is a front elevational view thereof; and,
FIG. 10 is a front perspective view.
The broken lines are for purposes of illustrating the environment in which the handle unit embodied in my design is used, and form no part of the claimed design.