"Rust"oration, material? Options

[14Maschine]

My floor boards got some rust. Infact one of me seat brackets came right off. So I pulled out the seats. No structural damage yet. It looks minimal to what ive seen. Mabey I caught it early enough. I will get to the point now
I may not need an entire floow pan and if I dont have to pay 115 bux for one I wont!
What steel could I replace the floors with? Perhaps I only need to replace small sections. Cold rolled mild steel? What gauge thickness?
I intend on using Mig welder.
I got some Naval Jelly. Couldnt find POR 15 at the hardware store.
Sugestions, comments, welcome!

[lapuwali]

POR-15 has to be ordered from them, although a few suppliers may have it. There are lots of other anti-rust paints now, too. However, if you can't afford a $115 for a new floorpan, you won't want to pay for POR, either. It's not cheap.

The floors are 1.5mm mild steel. 16g is close enough. Scrape and use a wire brush to get as much flaky rust off as you can to see where the actual damage is. If you really have to replace the entire floor, the Resto Design floor will end up saving you a lot of grief, so I'd save up for it. The end result will be much nicer. The indentations in the stock floor provide a good measure of stiffness to the floor, and replacing large sections with flat sheets will not help that.