I am not number plate concious and always struggle with references to registration plates. Please confirm that your vehicle is an x230 model. (1993 to 2002). The model number can be determined from the first three numbers of the VIN (see V5C reg document, or VIN plate on vehicle.) Also x230 has reverse above first gear selection.
For an x230, I think that you will need a switch with all 7 pins (blades) being the same size. This can be confirmed, by inspecting the connectors on the vehicle. Later Ducato models used a switch with six of the pins being smaller. From advertisements on eBay the x230 requires OE number 46543447, but I cannot confirm this.
For an example of what is available on eBay see
here. However I must warn that I had trouble trying to fit a similar switch to my x244 in recent years. I could not get the switch engage correctly with the steering lock assembly. I eventually purchased a more expensive unit, which to my relief just dropped into place.
For the electrical connections made through the switch in the various position see my attached diagram.