Disc brake Caliper pins/bolts sizes????? Where to buy???

The Caliper bolts/Pins on my a body stick out almost an inch to far when they are tight. They measure about 5 inches long from under the bolt head to the end. It seems I need some that are around 4-1/8 long. I can not find them anywhere. These are the bolts that the caliper slides the pads back and forth on, not the bolts that hold the caliper itself. I believe this front end set up is a 73 and up. Where can I find these????