I'm pretty sure that your ornament is a 1st year Sport Fury w/440 hood badge, hence the red white and blue.
Pot metal with a glued on foil plate for the numbers. Don't powder coat it.
Using the steps described above, clean it up - the chrome will look pretty good, and then use Testors model paints to do the colours. Buy sprays, and be patient - do one area each day and mask the rest off with good masking tape, cleaning up any over spray as described above.
Don't go for exact perfection on spraying the colour, as it was never that way originally - the manufacturer would have had little masking templates they just dropped over the ornament, likely one for each segment. A quick spray, swap templates, spray again etc...
The 440 numbers on the foil is a bit of a question - the raised numbers would likely have been in black, but I've seen blue and silver too. The outline would have been in a silver chrome maybe. The foil is a likely a light metallic gold, hard to replicate but I've seen silver and white too. Just gently clean it up, then pick out the numbers by cutting a piece of cereal box card into the shape of recessed area of the ornament, paint the card with paint and oh-so-gently touch it down in the area for a second. The paint should transfer to the numbers. Keep in mind that if you press too hard it will transfer paint to the flat areas beside the numbers as well... just clean it off and try again! Same process with the silver outline.
Here's a picture of a 66 Fury 383 ornament so you can get the idea of what I've talking about with the numbers area...
That was likely a fairly rare ornament, so have fun restoring it!