Uhm I'm pretty sure you can fish up a Chinchou from New Bark Town as soon as you get the Good Rod. If you're talking about Electabuzz or Raichu the Odd Egg you get from the daycare man can hatch into any of the baby Pokémon so you could get an Elekid or Pichu. Sadly we non-Japanese plebs only get a 14% chance of it being shiny instead of the Japanese 50%, so I don't tend to reset for a shiny.