They're in quite a few places. Mill Lake in Abby has largemouth, as mentioned Cultus has smallmouth. Albert Dyck Park/whamsley lake has both I'm told, my kid has only caught Larry's there though. Osoyoos lake has both - my youngest caught a decent large on a jitterbug a few weeks ago in osoyoos, while my other son caught a pair of smallies and a big carp. Vaseaux Lake between osoyoos and penticton is supposed to be a good spot, I'll be hitting it in a few weeks with my kids on our annual summer road trip...
Long story short, there are quite a few spots with bass. Which is good because my kids love fishing for em!
Make sure you check the regs (although it sounds like you already have). Some regions have banned fishing for them to reduce "private introductions", and only specific lakes are you allowed to target them.