Dear Ms. Montoya-Gajadhar,
Thank you for posting your request on History Hub!
Since International Nickel Corporation became part of Vale, you may want to contact the Vale Company in Canada to inquire about their archival holdings.
There may be records of the International Nickel Corporation and its dealings with the Canadian government. Therefore, we suggest you contact the Library and Archives Canada, 395 Wellington Street, Ottawa, ON K1A 0N4, Canada. The web site is https://www.collectionscanada.gc.ca/index.html.
We hope this is helpful! Best of luck with your research!