I’ll spare you the long sting off comments after this got posted. Basically people were telling the poster that he can do it himself(which is true) and that buying a whole new brembo caliper would be a massive waste of money.
You can go to any machine shop and they will happily take care of the snapped bleeder screw for $20 or a case of beer and you can be sure that your expensive Sti brembo calipers aren’t going to be ruined. Well besides you fucking them up yourself.
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Now let’s look at the picture of the rear Brembo the OP posted. Hmmm doesn’t that brake rotor look a little small? (The answer is yes.) Always double check part numbers even when you are buying from the OEM/Subaru. Triple check whenever you buy from an aftermarket supplier. It’s very easy to get a WRX sized brake rotor instead of the correct STi Brembo sized brake rotor.