B2b Lead Generation

Hi there, B2B Lead Gen in the US region. Need a lead list of 500 leads with the following criteria: Department - HR
Position - Manager/ Above Manager
Employee Size - Greater than 500 employees
Geography - US
(Have attached the type of data we would be expecting)

The Ideal Title - Community Manager, HR Director, HR Manager, HR Generalist, Social Impact & Community Affairs Manager

Keywords - "Volunteer time-off (VTO) Policy", "Corporate Volunteering", "CSR Volunteering", "Match Volunteer Hours", "Employee Volunteer Policy", "Volunteering", "Community service", "Employee engagement"

P.S. - Would be needing a sample list (with ~20-50 leads) to judge upon the quality in terms of precise email IDs, and closeness to the target group