Email Append service for FB audience?

We’re looking to use an email append service to find email addresses for our Amazon buyers based on their first name, last name, zip etc.

We’re not going to send them emails. We just want to use the email addresses to create a FB audience and lookalike audiences.

Can anyone recommend a good email append service? I looked at Accurate Append and they charge 15c/email, which seems like a lot.