Both Patrat and Lillipup (Route 1) give 1 Attack EV.
Every Pokémon in Dragonspiral Tower gives Attack EVs. Golett and Mienfoo each give 1 Attack EV while Druddigon gives 2 Attack EVs.
Golett can be found 100% of the time on Dragonspiral Tower 2F.
Otherwise, on Dragonspiral Tower 1F, Golett is found 50% of the time, Druddigon 30%, and Mienfoo 20%.
Basculin gives 1 Speed EV and can be found by surfing. For lower-level Basculin (levels 5–15), Route 1 or Route 3 is your best bet. Other locations include Pinwheel Forest (levels 5–20), Dragonspiral Tower’s exterior (levels 15–35), and Village Bridge (levels 25–55).
You can also use Vitamins or Feathers for at least a few of the EVs.
Hope I helped!