stewart wilkins at swrallying here in sydney,(if you could call windsor sydney,it's closer to perth in my opinion).i got a set a few years ago,plus getting another set in a car i bought,
& have been used in rally cars,so they have stood up to punishment.

if you're going to get somebody to machine the standard ones,make sure he puts a radius on the corners,because a right angle is an invitation for the part to crack & break at this point,resulting in at the least an interesting handling situation,if you could call it interesting,
& at worst an accident with serious consequences.