The following is from the Beretta's website -
"Bruniton is a proprietary high tech enamel finish. This durable finish provides maximum corrosion resistance when applied to steel parts."
What is a bruniton finish?
Several companies do refinishing work, they may can answer your questions.
Customized Creationz Custom Gun Works Shop
Robar Premium Finishing & Firearms Home Page
Rumor is that Stoeger will come out with silver or two-tone .45 cougar. Send an email to Stoeger and ask them, they are good about answering.
Contact Us - Stoeger Industries
Hope this helps.