132790 Ecommerce Solution

I have a web site done by others that needs an ecommerce solution attached to it. It already is at the stage where the first "My Cart" is displayed. This site uses oscommerce so you must be intimately familiar with it. Also we wish to use the Paypal Standard Merchant service to process the credit card payments. The site must go directly from the "My Cart" to the billing page and then back to the web site. No imtermediate pages will be accepted. The Paypal billing page must contain our header which we will supply. This project must be completed within 2 days and will be paid for once we can process a payment - no excrow. Please only bid if you have references specifically relating to the Paypal Merchant Service and oscommerce solution. We are looking for only experienced programmers.