Majority of "performance" parts are interchangeable within B13 Legacy platform which is any Legacy from mid 2003 to mid 2008, BL and BP chassis.
Keep in mind that yours is a facelift and some of the interior/exterior parts are different - different grilles/bumpers, different stereo/steering wheel/instrument panel etc.
Rear springs will have different ratings between sedans and wagons, sedan mufflers will have shorter tips and will be slightly tucked in under a wagon bumper (still a direct bolt-on). Front swaybars will differ between turbo/NA versions, rears are all the same, the same will apply to aftermarket bracing (underbody only), strut braces are all the same.
Are you still talking about Legacies?