Hub centrics are for bigger than stock bore.
Those 57mm bores are 14m smaller than our cars, they would never fit. It's not a good idea to machine the rims either.
if you are going to get a good deal on the wheels literally anyone with a lathe can open up the hub bore for probably like $20/wheel max. it'll take them a half hour.
As someone that runs a lathe 55 hours a week... It's not that simple.