It really depends on the facility where you are or want to be employed. Some hospitals have both RN and RPN's as scrub nurses. The hospital where I am employed, only has RN as scrub / circulating nurses. Years ago, they did have RNA's (RPN's today) as scrub techs. Either can do the job. I know that in London, ON they have RPN's in the OR as scrubs.
For a course in perioperative nursing, you will have to check out your local community college or others in Ontario. In Toronto, Centennial college offers a perioperative certificate for the RPN. You can call 416-289-5303 or 416-289-5000 ext. 8055. I know this because I just rec'd there continuing education calendar in the mail.
Best of luck. Hope this helps.