Subaru Printed 2.0 1998

I took my subaru to the technical service for the alignment but they could not align one of the rear wheels because a iron where the alignment was rgula was more hunched out of the common for a blow and I want to change it but I do not know what is the name of that piece I hope I could give me an idea of ​​what the pieces of that section are called to buy, I would appreciate them a lot.