hi does anyone know where i can source one for a td04 wrx bugeye?

basicly my car had an awful rattle,sounded like the downpipe gasket was blown however i traced it to the wastegate actuator i tried tightening the thread by half a turn/full turn but this did not stop the noise.

therefore i sourced a cheapy one on ebay and replaced-the noise was completely gone however due to it being cheap i believe its soft enternals are not coping with the cars power....

or can my original one be repaired atall? its just the standard one.