MPC brake question


I purchased a kart that came with a vented brake rotor set -up and mini -lite caliper , another kart I have I want to put this on , but with a standard caliper . The mini -lite came with an aluminum spacer for between the 2 caliper halves to make up for the wider rotor , does anyone know , or have seen a spacer for a standard caliper ? I did not measure the spacer ,but it is appox. 5/16 to 3/8 inches wide .