Pokémon Black and White 2

Well, I think I need to reform my team, I'm having a lot of problems to defeat Gym leaders, right now I have:

Lucario lvl 33
Magneton lvl 31
Azumarill lvl 24
Growlithe lvl 29
N's Zorua lvl 25
and a Hidden Grotto Miccino lvl 24, my problem is that I rely too much on lucario (I mostly only use him, the only other 2 that I use are Magneton and growlithe (which is very frustrating because I can't find a Fire stone....), I think I'll end up changing Azumarill for something else but I don't know what good pokemons are there for my team. I was thinking about Sandile or Ducklett.

[COLOR="#0000FF"]Pro tip, turn on your dousing machine at all times. ALL TIMES!
Turn it on and go the sand place before nimbasa city, and keep going there till you get to the area with the nurse in the front. Go to the bottom left of the map and you'll find a fire stone with your dousing machine. There's also a hidden thunderstone near the pokemon center if you use the dousing machine. [/COLOR]