Savage makes one. It's not camo or stainless like they make for the righties. But it's all black and looks nice. Is a 20 gauge. They don't make them in 12 gauge for southpaws. Its a Savage 19640. They run about 500.00 for just the gun.
Or you could buy my 870 slug gun I have in the classifies with a bunch of accessories and slugs for 500.00 lol