Its rare that they get broken when taking it out, most of the time is from people over torqueing them...In your case it might be hard, because the bolt is stuck...If it was broken the other way (putting it on) they are very easy to take off (because once broken there is no pressure).
I suggest getting the tool from Canadian Tire, or any automotive place, its your best bet...(and heating it up before will also help).
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