Preheat broiler. Place 2 avocado halves in a large bowl; mash lightly with a fork. Add mayonnaise and lemon juice; mix until well blended. Stir in crab, Karns Captain's Love Seafood seasoning, cilantro, chives, and pepper. Spoon into remaining avocado halves.
Place stuffed avocado halves on a jelly roll baking pan. Sprinkle with cheese and paprika.
Broil 4-5 inches from heat until cheese is melted, 3-5 minutes. Sprinkle with chopped cilantro if desired and serve with lemon wedges.