Take a photo and go to your local caravan dealer.
It will not be cheap.
You may also need to know if it has a pressure switch in built as well which is usually wires coming from the underside of the tap.
If it is a micro switch tap then it needs to be replaced with a micro switch tap. But if it is a pressure system, any tap will do. So there is a massive choice including domestic taps.
Conversion fittings on the ends of the tails will likely be required.