score:6
Yes, she can buy American Express Traveler Checks in Russia, and they would be accepted in Canada. The particular bank charges 2% commission, but she might find one which charges 1%.
Note, however, that this is not much better than having cash in hand in terms of proving she got funds. She can borrow $1000 from a friend, buy checks, go to embassy, then go to bank and cash those checks the next day.
As far as I know, none.
This doesn't prove at all the money belong to her.
She also would have to explain why she doesn't have a bank account. A consulate officer might suspect her income comes from illegal activities, or she's hiding it from taxation. Canada cares a lot about "being good moral character", so she should be able to address this.
Does she have a job, or had a job recently and has savings from it? She can go to her accounting department ("buhgalteria") and ask for the official salary statement ("spravka o zarplate"). She can do this even if she left the company. This would prove both that she has funds, and that they came from a legitimate source.