If you want to bring your mother to Canada on a super visa, then you need to wait until you are in Canada and have a job in Canada that meets the low income cut off. If you want to apply for a visitor visa for your mother now, a regular visitor visa is your only option.
It's impossible for any of us to say if your mother's application will be refused or approved. To be approved, she will have to demonstrate that she has strong ties to her home country and has no plans on remaining in Canada long term. Your mother should also be able to show that she has sufficient funds to pay for her trip to Canada.
If you want to apply for a regular visitor visa now, I would say she plans to visit for 2-3 weeks. If you say she wants to visit for several months, I think this will significantly increase the chances of refusal given her lack of travel history and the fact she is alone in her home country.