please be aware of the difference of primary coverage and secondary coverage. The two you mentioned above are secondary coverage carriers. They will only come into effect and pay out after you've exhausted primary coverage. You might want to consider a carrier such as Allianz that is primary coverage.. or something similar. Please Google the difference between primary and secondary coverage for travel insurance or any insurance for that matter
Never go through some of the brokers suggested here. They are not actually licensed but work off the licenses of others.... Ask to see the license in their name first.. Any company they would suggest you can apply directly with the company without having to go through these brokers at pretend to be licensed..
.. usually only the schools will get that for you now not the agents. You'll have to apply for a school pay the fee and then prove to immigration you're going to the school.