This is very achievable with JS and HTML5. We have done similar projects and are one of the approved HikaShop development partners. One example (with a different eCommerce extension) is this drum configurator, which lets the customer choose all sorts of different combinations:
www.snarekings.com/kingfigurator/
In that case there are hundreds of unique images being used (HTML5 and Javascript).
We are also currently working on another product configurator that takes a different approach. It's a custom graduation stole and pageant sash designer that has multiple images that layer on top of each other to create all of the potential color combinations. It's still under development so I can't share a link publicly, but each section of the sash (main body, inner border, outer border, fringe, rhinestones) are all different image layers. That way we don't have to create and store all of the potential combinations as separate images. The layered image approach is probably the way I'd recommend going for your unisuit product.
If you would like to chat about how this can work in your HikaShop store, please PM me here or contact us through our website (
www.PolishedGeek.com
)