Small modification to oscommerce site.(repost)

I require someone to make a small development to an existing OScommerce based site, hosted here: [login to view URL] The aim of the development is to enable a user to view a much larger image of each print. This functionality will only be relevant to images (products) that are for sale. The things that need to be done are: 1. Update the admin and database of the site to allow the site owner to upload a large image (currently they can upload a thumbnail and standard image) 2. Add view larger link (see attached [login to view URL]) which opens a large image in a popup div. 3. Add watermark to larger image dynamically using something like this: [login to view URL] ( see [login to view URL]) Many thanks