If you want something to replace soda and don't want artificial sweeteners, flavored carbonated water can scratch that itch. There's some that are low sugar and some that are no sugar. They have some really interesting flavors, too. La Croix is not a great brand, in my opinion.
All sparkling water costs significantly more than it used to before ~10 years ago. Safeway brand is my go to, but I miss those being like 3 bucks for a 12 pack.