kelsey hayes caliper bolts
A guy up in Canada once ran a batch of them off, a few years ago.
But don't worry about it, if you can't find any factory, original, used ones out there in the nation.
Regular hardware store, grade 8 bolts, will work just fine.
I think the size is 7/16 diameter, 1 3/4 inch length, fine thread.
I at one time thought you absolutely, gotta have, gotta use, factory style bolts, but in the real world, in car repair, car maintenance, you don't hafta.