Door Sill Rocker Panels

I removed the plastic cover panels on my rockers, and found they covered a multitude of sins.
Those covers hold a lot of dirt, thus retain water, thus promote rust.
I’d recommend to all to flush out those rockers and make sure they are not collecting dirt. Pull them off and spray undercoating in there.

My steel rocker panels under the plastic are about half gone, crumbled away.
I love this car and want to save it if I can. Not sure what parts I need besides the rockers.
Has anybody else dealt with this? A source for new rockers? Part numbers for a 2000 model?