In a large pot over high heat, add the oil. When the pan is smoking hot, add the shallots, celery, and bell peppers, saute for 5 minutes. Season with salt and pepper.
Add the tomatoes and garlic, saute for about 4 minutes.
Stir in the stock, and add hot sauce, bay leaves, oregano, and thyme. Bring the liquid up to a boil, about 8 minutes. Reduce the heat to medium, continue simmering for 15 minutes.
While the stock is simmering, break the sausage into small pieces and cook in a separate pan until browned.
Skim the impurities from the top of the gumbo, turn the heat to high, and cook for five minutes. Fold in the oysters and sausage, reduce the heat and simmer for 5 minutes. Add water, increasing or decreasing to achieve desired consistency. Remove from the heat. Remove bay leaves and discard.
To assemble, ladle the gumbo into a bowl and top with rice.