Your budget is modest for that kind of project (custom build kit designer + integration) but contact me i might figure out something (i create kit designers with my team). Another option you should check (if not already done) is “Fancy Kit Designer” , see if you can make it works for your project. It’s only 40$ the plugin if i remember well. But it might not fit exactly what you need or you might find difficult to integrate it with your website.
Thank you for your reply. It would be appreciated if you could offer a Demo for us to practice. And is it possible for us to download the designs done by the cyclist on the platform?