I don't think bars for previous generations will fit... If I am not mistaken they are a different shape and mount differently as well. I know the end links for previous models will also not work in the rear.
you would be looking for a sway bar that is meant for a 08+ STI, but there is no benefit to buying an OEM one as they are the same as what you have now.
I went with the Eibach kit 7718.32
you would be looking for a sway bar that is meant for a 08+ STI, but there is no benefit to buying an OEM one as they are the same as what you have now.
I went with the Eibach kit 7718.32