custom t-shirt tool for Zen cart

I am looking for a simple "custom t-shirt" tool form my zen cart webiste. The Reason I say simple is because currently seeking for using clipart to develop new designs on my site. All this tool has to do is use my clothing in several colors, and add from a list of Prints to be added to the clothes. The tool should do the following: - Fit in my current website design -Ability do choose several products and then choose a color - Choose from a list of MY existing designs to print on the t'shirt - - The design must show up on the image of the T-shirt - I wholesale so each product must show QTY discount (basic with zen cart) example 1-2 $15.00 3-5 $10.00 6+ $8.00 -It must function well and be easy to use for both the customer and me. You must be able to show me that you can do this and worked with zen cart, and maybe show me some work you have done. I'll be happy to answear any other questions.