Brakes on Sport Fury

[58 coronet]

Hi. I got to checking the brakes on the Sport Fury. They were supposed to have been all rebuilt prior to me getting the car but not so. It has 12 inch x 2 1/2 brakes (front and back). Was this standard for a Sport Fury. In 59 Three plane brakes were introduced part way through the year. This is an early production car and so has single plane brakes. The problem is , three wheels are single plane and one front is triple plane. The brake cylinders are all new and for single plane. Does anyone have any spare parts after converting to discs. I would need a backing plate, shoe support and hardware for a front wheel. John