Payment Gateway setting in my current off line store

Dear Friends. My client have a website with php, mysql database hosted on linux server. my client sale handicraft items on website. Right now we work in domestic market. We have many inquiry from many other country. My client shopping cart work properly. Now i want set paypal payment gateway in my client site. I will give you FTP details and paypal id to selected bidder. My budget is very low not more then $50.00. Right now we have many project from other company so we outsource this work. Happy bidding. Thanks