Build a One Page Chargify Subscription Page - PHP

I need a one page Chargify subscription page. It needs to use the API ([login to view URL]) and all I should need to do is enter my API credentials. It needs to allow the user to create a new subscription with their credit card. I have three different plans, so it needs to allow the user to select different subscription plans. It needs to have the form with all the correct text fields. I can pay $20 and need it don ASAP