Based on this product's specifications, here are some alternatives and similar models
Keyboard Dell KB312948 QWERTY layout Black for E5540
Summary description:
Replacement keyboard Dell KB312948 designed for Latitude E5540 laptops. QWERTY layout in black finish provides standard key arrangement for typing and system controls. OEM part with original MPN KB312948, suitable for repair or upgrade of compatible Dell E5540 units to restore full keyboard functionality and reliable input performance.