Simple graphic design plugin for website

Selling custom doormats, where the users can set the color and the text written on it themselves. I'd like to include different features like font types, sizes, and position of the text, and maybe even more. Is there maybe a simple freeware design company such as PhotoFiltre or others that offer a plugin or something that can be integrated into the website to allow for something like that? Or might there be a simple alternative with which this could be accomplished? Cheers