I'm a fellow Canadian from Toronto who's been flying for 45 years. Your local flight school near Sarnia doesn't offer Sport Pilot training because it DOES NOT EXIST as a program or licence/permit in Canada. Did they not tell you this? Very odd. It's strictly an American thing.
Here are your options: The closest Canadian programs to it are an Ultralight Pilot Permit(AULA-Advanced Ultralight Aircraft), a Gyroplane Pilot Permit, a Recreational Airplane Pilot Permit(sort of Private Pilot Licence light), a Glider Pilot Licence and a Balloon Pilot Licence.
My recommendation to you is to take the Recreational Airplane Pilot or Ultralight Pilot because they 're much cheaper and require far less hours to complete. Of course there are restrictions compared to a Private Pilot Licence.
Go back to the Sarnia flight school and talk to them about the Recreational. For Ultralight, google Ultralight Pilots Association of Canada(UPAC) for a listing of flight schools that might be near you.
One more thing. Don't rely on this EAA Forum for Canadian oriented or relevant info, you'll just be completely misguided(through no fault of EAA) into thinking for whatever reason that what is done in US general aviation is the same as Canada. Nothing could be further from the truth. As a newbe go to the Recreational Aircraft Association of Canada site.