The ornamental design for a waistbelt or similararticle, as shown and described.
FIG. 1 is a top plan view of a waist belt or similar article showing my new
design;
FIG. 2 is a bottom plan view;
FIG. 3 is a left side elevational view, the right side being identical
thereto;
FIG. 4 is a top and left front perspective view; and
FIG. 5 is a top and right, rear perspective view, the broken line showing
of a container being for illustrative purposes only and forms no part of
the claimed design.