If those are the screws I think they are, you won't find a screw extractor small enough.
If it was mine, I would either drill out the screw or just punch it through. If it is actually in a piece of the aluminum framing, drill it out, small bit and keep going up. Odds are once you get close to the screw size it will stick to the bit and spin out in the bit. It is not hardened, so you will not need special bits.
Then I would check a few more for rust. Any rust, replace them all.