The ornamental design for a stirrupleather for an equestrian saddle, as shown and described.
FIG. 1 is a front top perspective view of a stirrup leather for an equestrian saddle showing my new design;
FIG. 2 is a rear bottom perspective view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof;
FIG. 5 is a side view thereof;
FIG. 6 is an opposite side view thereof;
FIG. 7 is an enlarged front view thereof; and,
FIG. 8 is an enlarged rear view thereof.
The even-length broken lines represent stitching which form no part of the claimed design. The stirrup leather for an equestrian saddle is shown with a symbolic break in its length. The appearance of any portion of the article between the break lines forms no part of the claim.