Non-operating provincial parks offer limited recreational experiences, fewer/no facilities, and generally no dedicated staff or fee collection. These are generally located in undeveloped wilderness areas. 

For a full list of Non-Operating Parks visit: Locate Non-operating Provincial Parks in Ontario

For further information consult Provincial park management direction statements for each park, these may show you where authorized sites are located.

Here is a great break down on camping on Non-Operating Parks in Ontario by TheKasPack.com

To see whether camping may be available at a park. Go to the parks page on OntarioParks.ca and look for the following icons under Facilities/Activities 

The site indicates which activities are permitted by highlighting icons in blue. The grey icons mean an activity is not permitted.