Cook bacon in a large Dutch oven until crisp; remove bacon, reserving 2 tablespoons drippings in Dutch oven. Crumble bacon, and set aside.
Melt butter in hot drippings in Dutch oven over medium-high heat; add leeks, and saute 5 minutes or until tender. Add wine; bring to a boil. Reduce heat, and simmer 10 minutes or until reduced by half. Stir in fish stock and next 3 ingredients; cover and simmer 20 minutes. Stir in 1 dozen oysters.
Process oyster mixture in batches in a blender until smooth, stopping once to scrape down sides; return to Dutch oven. Bring to a boil; reduce heat, and stir in whipping cream, remaining 3 dozen oysters, lemon juice, and next 3 ingredients; cook 1 minute. Sprinkle each serving with reserved bacon and chives.