Obtain Lava from Villagers and or Wandering Traders

I have been playing a super flat survival world on bedrock for the past couple of days and trying to figure out how to get lava to get stone and go to the nether. It seems impossible as Structures don't spawn, No Villagers Trade it, and You can't get it from Wandering Traders. With all that said my suggestion is add Lava Bucket as something you can buy from the smithing villagers (Weapon Smith, Tool Smith, and Armorer) or add it to the wandering trader trades.