Buy a new Sim

Dear Sir,

        My name is Ahmad. I am living in Pakistan. But my Business in USA. I am exporter. I have registered a company with EIN in USA. I need a USA Phone Number for use in pakistan, i need the US number for receive the sms and call from US Banks and receive the call from USA local numbers and international numbers for my business. My manager live in NEW YORK. He can receive the sim and ship to me in Pakistan. Please let me know that i can buy the USA Sim card with active international Roaming?