Old thread but.... With some small exceptions in the bridge and brake hose attachment area, those calipers look a heck of a lot like the early version 6 pots used on some AMG Mercedes.
$4.5K? Wow, everything is spendy down there. I realize that's for calipers/rotors/mounting brackets, etc., but still! I bought a pair of the same calipers in the US for $730 in 2009, and they were practically brand new.
AMG Mercedes... ignore the OEM mounting bracket.