I have "doctored up" a bumper before just to get by for a while until a replacement could be found. I peeled off the pieces of flaking chrome along the lower edge, then cleaned the bare steel with coarse steel wool and a wire brush. I treated the bare metal with a rust killer product, then painted the bad spots with silver paint. I cleaned the over spray off the good chrome with fine steel wool. The result was not pretty in good light on the bench, but, installed on the car, it looked fine until you laid down and looked at it close up. The silver painted parts didn't stick out like a sore thumb the way the rust and bubbled chrome did.