If you are on a limited budget, your best bet is this Topshop Duster Coat. It's a wonderful product, while not very costly. Another strong contender for your wardrobe is this Topshop Duster Coat. While the price of this piece is not very high, it will definitely attract a lot of attention.
If you want to splurge, then what you're looking for is this Fuzzi Duster. It's more expensive but worth your money. Why not take a look at this MCQ Duster too? Expensive, but worth every penny. In this price range, you can also consider this Isabel Marant Duster. You won't regret the money spent!