Use Arcanine and Medicham. Arcanine will be a pretty good lead (level it up though) against Weavile. Medicham's wallbreaking capabilities can easily 1 or 2 shot Walrein with High Jump Kick. Replace Lunatone and Seismitoad. I can't really see the being of better usage than Medicham and Arcanine.
Possibly Vaporeon to pass wishes? I would drop Iron Defense on Scolipede (give it Megahorn) and give Vaporeon Acid Armor, Baton Pass, Wish, Protect/Scald/Toxic.
Miltank is before Gym 10. Not sure about Vulpix.
Spiritomb has been axed to after the 10th Gym iirc. You need to get an Odd Keystone first (from mining, I think)