I'm working the movie shield right now actually
Before the movie even started up I had been working on my own version of a Capt America suit, and my idea for the shield was very similar to what is in the movie, the only difference is how they did the back straps.
So I am working on an anodized aluminum one with grooves very similar to the film. This one is 26" though the film one looks slightly smaller in the newest released pics.
Here is mine so far, haven't gotten the grooves in yet or anodozing, but the lines are on.
working on some aluminum finish types and the lines are added on for the groove pattern: