I googled
made for prius c ?

Personally I use something like this in all of my vehicles. $10 at Autozone. They have three sizes. Buy one and try it. If it doesn't work return it and get the bigger or smaller size. One of my vehicles they are perfect. One they were a bit small and needed the sunvisors to hold it up. And my 78 station wagon they are a bit big but still fit really well with no help from sun visors. Can't really beat it for $10