The ornamental design for an endoscope handle, as shown and described.
FIG. 1 is a front perspective view of an endoscope handle showing my new design;
FIG. 2 is a left side view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a rear view thereof;
FIG. 5 is a front side view thereof;
FIG. 6 is a top view thereof; and,
FIG. 7 is a bottom view thereof.
The dash-dot-dash broken lines that are shown in the endoscope handle disclose boundaries only and form no part of the claimed design. The dash-dash broken lines shown in the endoscope handle are for portions that form no part of the claimed design.