Toss the shrimp with the lemon juice and 1 teaspoon Old Bay seasoning in a medium bowl. Whisk the sour cream, mayonnaise, chopped pickles, the remaining 1 teaspoon Old Bay and 1/4 teaspoon each salt and pepper in a small bowl. Set aside.
Cook the bacon in a large skillet over medium heat until crisp, about 7 minutes. Remove to a paper towel-lined plate and discard all but 1 teaspoon of the fat in the skillet. Return the skillet to medium-high heat. Add the shrimp in a single layer along with the liquid. Cook, flipping the shrimp halfway through, until opaque and cooked through, 3 to 4 minutes.
Lightly toast the potato bread and spread each slice with the sour cream mixture. Sandwich with the lettuce, tomatoes, shrimp, pickle slices and bacon. Serve with potato chips.