Either Fry Electronic or dig thru the Yellow Page for local electronic shop.
A rocker type switch shouldn't pass current.
If you are around central OC, there are 2 places I know of. Sav-On electronic on Harbor Blvd and 22 Fwy and JK Electronic on Westminster Blvd between Edward and Springdale/405 Fwy.
Well other place you should try is local autopart places Kragen, Autozone, Pepboy. They all have switch for lights. Pepboy have some nice looking one.