I stand corrected. As to the brake caliper, you can try rotation of the spring to bend it out a little. You might also check that you have the proper spring in that arm. Springs come in left and right for cantilevers. You might also look into replacing the springs. The springs aren’t universal but you might be able to find something that has a spring that is close enough. Finally, you could look into a better cantilever if you can’t make these brakes work. Cantilevers with adjustment nuts like the Paul’s below are easier to balance.