If you're looking for an affordable item, your best bet is this Herschel Duffel Bag. It's a wonderful product, while not very expensive. Another strong contender for your wardrobe is this Filson Carryall. While the price of this product is rather reasonable, it will certainly attract a lot of attention.
If you're looking for something in between pricewise, why not opt for this Karen Walker Carryall. While the price is very reasonable, this piece is an easy wardrobe update.