Zesty Marinated Shrimp & Artichokes

1/4 cup white balsamic vinegar
2 tbsp parsley
2 tbsp finely chopped green onion
3 tbsp olive oil
1 packet garlic-and-herb dressing mix .75 oz (Good Seasons brand or the like)
1 lb peeled and deveined large cooked shrimp 21/30 count
1 14 oz can artichoke hearts, drained  and cut in half
1 cup olives (black or Kalamata)
1 cup halved grape tomatoes
1 cup fresh mozzarella, cut into cubes or crumbled feta
Small fresh basil leaves, chopped

Whisk together vinegar and next 4 ingredients in a bowl. Stir in shrimp and next 4 ingredients. Cover and chill 8 to 24 hours. Stir in desired amount of basil just before serving.