I don't know how many exactly, because I think the intent was to implement it gradually—advancing or postponing the age of retirement or eligibility for elderly benefits by two months per year or something like that. It would have made a difference to probably thousands and thousands of seniors.
Evidence of meeting #65 for Government Operations and Estimates in the 44th Parliament, 1st Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was budget.
A video is available from Parliament.