Hello houhuantom,
There is a simple explanation for this: Wholesalers don't often list their bulk prices on their website. You will need to login or contact the wholesalers to view prices. Wholesalers do this to protect retailers like you.
It's so worth spending 5 minutes to sign up with wholesalers (or email then directly) and see how much the items are at different order volumes.
Try that and let me know how it goes.