I live (and was born) right next door in Ontario and here "SRS" (or GAS - Gender Affirming Surgeries as the term that is being used more commonly these days) can include orchiectomy as well as any other trans-related surgery including top surgery (mastectomy with chest reconstruction or breast augmentation). That said, not all surgeries are covered by health care (OHIP) up here (the most notable exception being FFS).
At the present time, all one needs to legally change the gender (sic "male" / "female") on their ID is a letter from a physician attesting that this person identifies as "x" gender. I believe it was in 2013 that the previous requirement of having to have a "transsexual surgery" (which, for the record was never actually defined) was deemed by the courts to be a violation of human rights. So largely, the way this is operationalized in this Province is that anyone who has socially transitioned +/- hormones (though being on hormones will help assuage concerns that a physician may have about how "serious" one is about living in a particular gender) is able to legally change their gender.
Cheers!
Rebecca
Toronto, ON
35 years old
Transitioned socially 1997
Hormones since 2002
GAS (vaginoplasty) Montreal (Brassard) 2008
FFS (forehead/nose) Buenos Aires (Rossi) April 2016