If you are an Ontario resident, for your SSN, see if the Niagara office can help you. See if they offer a less rigorous option to merely provide your 9 digits to you over the phone/in person (once you’ve established your identity to them) versus obtaining a tangible replacement card via the more involved form application process (since for your tax return filing purposes the former should suffice).
Further, there's an alternative method - ONLY for certain selective Social Security Office services - that saves the trip to Niagara Falls or Buffalo. One has to make application through Toronto's "local" Social Security office, which is in Niagara Falls, NY. One can do so either by going there in person or by phone (1-877-480-4992). Be prepared to redial and redial, and then wait on hold. Once one gets through to Niagara Falls NY one can request an appointment to be interviewed over the phone at an agreed upon time and date. They will phone you at that time. This interview takes 20-30 minutes.
The Niagara Falls Social Security office is located at 6540 Niagara Falls Blvd., Niagara Falls, NY 14304, and may be contacted at 716-283-1066 (1-877-480-4992) or click here to locate another Social Security office. If you are not required to go to a Social Security Card Center, you may visit any Social Security office convenient to you. National Toll-Free 1-800-772-1213
See here information for the Ontario numbers and the Niagara office contact info (Fax 1-716-283-1774) or click here to locate another Social Security office.