Not necessarily as those surrounds are readily available, I have installed four new ones all matching. The only way is to start by taking the switch off - use a small screwdriver in either of the slots - there are two, one on each opposite side, slight twist and it will pop off. You can see the slot near your finger, I think.Yes it does match the fitting of all the other switches in the van so I think it is original. Cheers
Two small cross headed screws behind secure the switch to the inner surround. Take those out and pull the switch forward.
Check whether it is in fact wired in, or is redundant.
If wired in, check with a multimeter which terminal is “live” if any - it should be a 12v supply on one, if it is connected.
Finding out where the other wire goes is more of a problem, there may be a clue in the thickness, it should be fairly thin, but if someone has wired an inverter activation using that switch who knows ?
I hope that gives you a starting point, good luck and welcome !