I believe thats a nickel version or it could be hard chrome . The one I'm thinking about is just like that , but it also has some engraving on it . From the advertisement the engraving appears to be from a machine or lazer so it wouldnt be as pricey from there custom shop .
I can't find that colt advertisment any where on line , but its in this magazines all the time . Even in Colt catalog they offer the nickel and blued / case hardened color but the chrome is special order .