The ornamental design for an endcap for ledreplacement bulb, as shown and described.
FIG. 1 is a top perspective view of an end cap for LED replacement bulb embodying my new design;
FIG. 2 is an end view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a side view thereof, the opposite side view being identical thereto;
FIG. 5 is a bottom view thereof;
FIG. 6 is an end view opposite FIG. 1, showing an interior of thereof, the interior being unadorned and forming no part of the claimed design; and,
FIG. 7 is an illustration showing two end caps on a LED replacement bulb for environmental purposes only, the LED replacement bulb forming no part of the claimed design.