Expert joomgallery ( Joomla)

Hi this website is on joomla 1.5 it still working fine you must know joomgallery so i ve made a gallery website with 3000 images, where everybody can download it, but if those images are used for any resale product or free distribution they have to purchase the license. i ve virtuemart as well that sells only one file, the license. so with the license purchase you can use any image on the website forever [login to view URL] what i want do now, is change this policy i want the button "add to cart" in every page, so the customer can buy every single image license. the hi resolution images are always available. they buy the license for legal pourposes. so when they add it to the cart, i will like the thumbnail of the texture in the email, like a list, like an order, the customer can buy many images as he want. that's it every image same price you already have the ecommerce component, and the gallery component, we need just to make some functional changes