Oh man thank you so much! I've spent so long trying to find out what that bolt is. I think I might have that on hand since I went to O'Reiley's and they helped me out as well (I just haven't tried them yet because it was a fairly long day). Might get a few extra though and probably a tap and die...
I'm sorry to revive quite an old thread but I've been trying to figure out what that bolt is that attaches that bracket to the arm like that. I just replaced my front brake pads and rotors and one of them screws stripped out and I've been looking everywhere for it. I own a 2020 4Runner