Cliffy for the kickout, mylar circle for the magnet and pinbit plastic protectors. While you are at it buy some extra post rubbers as they wear out fast on this game. I went with the superband post rubbers that are clear which are lasting really well but they do play a bit different (much more bouncy).
The pinbits protectors is a must with all the airballs. Be advised the one under the warp ramp is a PITA to install.