Add/Modify on OScommerce based site

I want to add a feedback collection feature on my OSC-based site. After finishing order with customer, a mail inculding a link will be sent to customer. The link leads customer to log onto our site and write feedback to specified order. And, the feedback could be checked by both customer(in front-end) and admin(in back-end). Besides, there are some minor modification to some existing features, setting up period of validity for shopping cart, adding a radio button for removing content in cart, etc. It is difficult and also time waste to describe related details without spending some time on checking the site. Since I'm looking for a long-term copartner for my existing and future projects, I want a professional PHP coder with good coding habit, and be experienced in oscommerce, and if you are familiar with Javascript, it is better. With above requirements, if you are interested in and able to do it right now, please write to me for more info.