Well, we need some more information.
-What model year Legacy GT transmission is in your car?
-Is it a normal Legacy GT transmission or a Legacy GT Spec B transmission?
Here is what I'm seeing:
https://i.imgur.com/WNBjVFa.png
https://www.rallysportdirect.com/sc...=Drivetrain > Clutches > Single Disc Clutches
Seems like some are interchangeable. Aside from looking at fitment specifications, your situation is more complex since you have another model's transmission. I would suggest sticking with the Legacy GT specified clutches. However, I haven't done any research, so it's up to your own due diligence.