Wouldn't it be easier just to buy a new starter assembly from RockAuto and just replace?
http://www.rockauto.com/en/catalog/subaru,2008,legacy,2.5l+h4+turbocharged,1440457,electrical,starter+motor,4152
http://www.rockauto.com/en/moreinfo.php?pk=7946208&cc=1440457&jsn=495