Place sardines in a shallow dish. Top with olive oil, 1 1/2 tablespoons herbs, and lemon juice. Turn to coat. Cover with plastic wrap, and let marinate in refrigerator for 30 to 60 minutes.
Heat a large grill pan over high heat. When grill pan is hot, spray well with cooking spray. Season sardines with pepper. Place on grill pan, and grill until golden brown and cooked through, 1 to 2 minutes per side. Remove to a serving plate.
Sprinkle sardines with parsley. Drizzle with sherry wine vinegar; serve immediately.