The switches Van's uses in the RV-12 are manufactured by Otto. Below is a link to the data sheet for the K2 series of switches. If you look on the side of the switch, you will see the part number, use the Otto K2 switch chart to decipher the type of switch you have (for your information). Not that you need to do that ... because if you order using that EXACT part number on the switch, you will get the proper switch. https://www.otto-controls.com/-/media/products/electromechanical-switches/rockerswitches/k2sealedrocker/k2-snap-in-rockers-catalog-page.ashx
Once you know the number, you can try a Google search to see who stocks the switch if you don't want to order from Van's. I did this when I added two switches (fuel pump and left landing light) to my RV-12.