Stuart & Wright has three Jerome Dreyfuss Billy Bags on sale for $660:
All of these are the large size, which is the same size Billy Bag that I have (see outfits for real-life pictures). At first, I was concerned it would be too big, but when I use the shoulder strap, it’s much more manageable. And when I do need to carry more (like when traveling), I use the handles and can carry a TON of stuff, very easily. The Jerome Dreyfuss Billy bag is a classic bag, totally worth the investment (especially on sale!).