Sunflowers only tolerate a very short time indoors - and, then they have to be transplanted.
I don't think they put up with a pot even for as long as squash or melons. They don't transplant all that easily, either. If you are attentive to beginning to hardened them off at the right moment, then carefully transplanting, they may do fine.
A little challenging.
We are each other's harvest; we are each other's business; we are each other's magnitude and bond. ~ Gwendolyn Brooks