Not sure what you want but IMO the levers will probably cost more than a new faucet so maybe explain what is the reason for doing this this way.

Levers on a vanity and not replacing a faucet? I am confused.

Handles, levers on a faucet, installed in a vanity?

Are you in the US?

I suggest you inquire with the faucet manufacturer if it can be done and if they have the needed levers.

Yes. Many popular manufacturers make replacement levers. They are usually a standard size to fit on many faucets. Easy to install.