If you missed the Express sale, there's a really similar jacket at Forever 21 right now for $24.80. It looks ridiculously pink on the F21 website but in person is much more of a dusty pink and only a tad bit lighter than the Express jacket.
http://www.forever21.com/Product/Product.aspx?BR=f21&Category=outerwear&ProductID=2078968353&VariantID=
Comparison with the Express jacket (Express on left, F21 on right)
Personally I prefer the fit of the Forever jacket because it's less boxy but on the other hand the Express jacket is shorter which is more like the actual Topshop jacket.
Also, I found a shirt that looks a lot like Amy's in Girl Who Waited...and naturally, because these things never work out perfectly, it's a man's shirt. It does come in a million sizes though so perhaps it could be taken in to have more of a women's fit?
http://us.asos.com/ASOS%20Polka%20Dot%20Chambray%20Shirt/wvvwr/?iid=1764550&SearchQuery=dot%20shirt&sh=0&pge=1&pgesize=20&sort=-1&clr=Blue&mporgp=L0FTT1MvQVNPUy1Qb2xrYS1Eb3QtQ2hhbWJyYXktU2hpcnQvUHJvZC8.
P.S. Somewhat related: I got my AA dolman hoodie today! It's enormous (goes to midthigh)! And I love it! Thanks
ultimateginge for posting a 30% off coupon :)