I checked the site it says that a round trip fare (so from Van to Kelowna and back again) would be $119.52.
But if you purchase the tickets 7 days in advance then the fare is $85.60, and if you purchase it 14 days in advance the fare is $68.48, so certainly not hard to come up with that at all.

Now for me to come there from where I am it would be $101.65 if purchased 14 days in advance. Don't think I'll be coming by bus, LOL