that actually does look pretty good
if you can get it for $500, i'd probably go for it.
but it's a TON of work to strip a car and switch everything over to a new tub!
at least you would get the color-change done right with that tub.
now, we need pictures of the rusty spots on your car.
how bad is it? rusted through the frame rail?
surface rust or real holes? how much? where?
grab a camera and get some pics for us.
Andy