Claydol's no worry either; it falls quickly to double surfs as well, or Surf + Razor Leaf. =P Really, it's Xatu you should be worried
slightly about, and an attack from the thing you used to wipe the floor with Winona will work. =P
HP - Whismur - Cave on Route 106
Attack - Carvanha - Route 119 (Super Rod)
Defense - Sandshrew/Skarmory - Route 113
Special Attack - Spinda - Route 113
Special Defense - Tentacool - Almost Anywhere you can surf
Speed - Zubat/Golbat - Cave of Origin
Look up to see how many EVs each give, and factor from there. =) Everywhere you can access has those Pokemon, though; Zubat are in almost any cave, after all. =P Also; remember, in Gen 3, the Phsyical/Special split hasn't happened... Is Bug type special, or physical?

4 Pokemon, so you can have two sets. 3 for Singles, 4 for Doubles, 6 for Triples, and also 6 for Rotations and Launcher battles, which follow the Triple battle rules. Also, that'd be problematic, unless you somehow had a friend willing to help remedy your Wi-Fi trouble. =/