I would not follow this process. it seems very antagonistic especially considering the fact the SINP does not advise of this routeEach province has something similar and they usually mail the documents and some in fact ask you to pay for return postage as well; its varies for each province. Now with COVID-19 the experience may be different. For e.g. for MPNP they asked for return envelope and postage but no other fees was charged.
Details here
https://www.saskatchewan.ca/residents/justice-crime-and-the-law/your-rights-and-the-law/make-a-freedom-of-information-request#making-an-access-to-information-request