As much as i admire the enthusiasm, i had a crack at this once. Unless you have no need to do anything else at all (Including eating and sleeping) i dont know how you'd pull it off in a week.
The Helmet alone has taken me a long time today (But i also work in short patches, so you might be better than i am)
Definitely not. Most armors you see here takes months to do. The best ones take years and im not paraphrasing.
You only have 5 components in your suit. I say it take about a month to pep properly and another one to harden detail and paint. Then factor in all the mistakes, weather and other life problems id say 2.5 - 3 months is what your looking at for this, at worst.
Trust me, you'll wish that you hadn't rushed. Take your time, do one piece at a time. No need to waste a week, cardstock, resin, fg, just for it to look bad.
Also, ACUs I believe aren't the BDU for this soldier. If I remember correctly it was more the black, gray and white BDU that you see with our other members wear with the Halo 2 ODST