Looking for a plug in that let's users specify custom dimensions and buy photos

Like the title says, I want a plug in that allows users to purchase photos from my site but I want them to be able to specify the dimensions, material, size, etc. I’ve searched but all the plug ins I’ve seen require you to have pre-determined dimensions which the user then selects. At first I was going to just have them contact me if they are interested and then I can ask them what they want. But I want them to be able to order straight from the website and allow them to customize their order. Any ideas of plug ins that could achieve this? Any help is appreciated!