This is a condensed version of how it's done.
This set in the pic,were corroded even more than yours. Restoring them is very time consuming and requires lots of masking and a bead blast cabinet but, they turn out very nicely as long as the lenses aren't cracked and broken.
The top,flat part that gets so corroded first gets bead blasted,then I lay a sheet of 220 wet or dry on a known FLAT surface and start sanding till they are flat. I then fill the corrosion holes with Permatex "LIquid Metal" comes in a tube. Then, sand again and repeat til the holes are filled and flat. I paint that flat part with several light coats of "chrome" paint.
On the inside metal parts, I first mask off the lens and paint the metal parts of the bulb holder with spray "Matte Nickel" available at Home Depot. After that is dry I go back in and paint the reflector part "chrome" with a small brush.
PM me if you want me to redo them for you.
Dan in Colorado