Pumpkin Corn Chowder with Shrimp

Name: Pumpkin Corn Chowder with Shrimp
Ingredients: 3 tablespoons butter; 2 tablespoons minced shallots (or may substitute minced garlic); 3 cups corn kernels (fresh, frozen, or canned, drained); 1 quart 4 cups chicken stock or broth; 1 can (15 ounces) pure pumpkin purée; 2 pounds uncooked shrimp (thawed, deveined, tails removed, and roughly chopped); 1½ teaspoons kosher salt; ½ teaspoon ground black pepper; 1/8 teaspoon Old Bay seafood seasoning; ¼ cup half and half (or milk); 1 teaspoon freshly squeezed lemon juice; ½ cup uncooked orzo pasta