Hi
We added the option to recalculate all available inventory to our bundling app: https://apps.shopify.com/bundleup
If you bundle up each variant as you would need to in this scenario each variation qty available will be calculated from the component stock. So if that component is on 100 variants every variant would reduce as a component gets sold.
Happy to help guide in setup and testing so just get in touch.
Regards
Tom