Faulty Oil Level Sensor?

[VolksKid83]

The oil warning light and the 'low oil' warning message on startup have become a permanent feature on our 2003 2.0 Passat.
The oil level is correct. So removing the plug from the oil level sensor, cleaning it with contact cleaner then reassembling fixes the issue for a few days of everyday use, then the warning reappears and doesn't go until i repeat the exercise.
The wiring by the sump looks ok and so does the connector. So dodgy level sensor?

Also, I'm looking at where to get a new one, am i better going for a genuine second hand item, or a brand new patern part?

Cheers guys!
(And happy new year!)