How to build a product configurator like described below, or where should I look for assistance

I am working on a webpage for Parts for RC cars that I make. I am not a coder and know just enough to be able to tweak my css and be dangerous. I am using Joomla cms and a shopping cart called j2store. Each product has up to 7 different regions that at the moment could have 7 options each, but in reality could be up to 40 options per region. As such there is NO way I could make a separate image for each variation combination. The Shopping cart I choose to use allows me to set up options and have multiple options per product without generating the tens of thousands of separate variations of the product. Mt need it to make it so that when the option is chosen it uses a php function to change the specific region it is mapped to to the color they have chosen to give a visual preview of what they want. I know this is above me but with tools and materials I am working with a near ZERO budget. Where is the best place to look for help in this situation? My first thought is to do multiple png images stacked on each other with only 1 region in white and the rest in transparent. I could do the image stack using div relative and absolute, but I have NO idea how too go about doing the php or jquery or whatever to link their choice the the color change action.