Front Headlight Switch

Hi have a faulty sliding headlight switch lights will not go up or down does anyone know where to get a new original light switch.
Have bought a light switch from dg rally which can be adapted but autotrician did not recommended and asked me to get original switch.
Can anyone help or advice me on this issue.
It was good all meeting up at Bridlington looking forward to next national meet
Ray and Wendy

You may have already done this but check its not another component - wiring, relays, fuses, motors etc before condemning the switch. A simple multimeter to check the continuity of the switch, or connecting the wires together (be sure you study a wiring diagram before attempting this) would be a worthwhile check.