If you have a link stone, maybe consider a Kingdra with icy wind to wear down hawlucha and cut its speed. Zebstrika might get the KO after that, or even Krookodile plus it's gonna get the moxie boost too. Since your sharpedo doesn't have speed boost maybe it'd be better to swap it for Kingdra or Krookodile. If you can't get kindra, try teaching sharpedo icy wind. Also getting all your mons at lvl 65 or whatever the lvl cap is, i going to help a lot. Yes, grinding is tedious, but you gotta do what you gotta do.
As it was already mentioned crustle, can be useful, just don't use a move that makes contact on hariyama. Braviary with sky drop, can basically render one of the opposing mons useless for a turn, and mienshao with fake out is always helpful too.