Well you can find two solutions in this thread, which are not the best, but kind of work.
With the Accessoires modul, you can use stock management, but as said, But then the website must load each time you choose different color.
A real solution for this, should come from the Shop itself. In List or grid mode, you should have the option what to show. If the shop can scan a category for each product and show it, then it should be able to scan for each color combination and show it as single product.
In the new presta version the shop is able to show color combinations when you hover over the product image in grid view. Based on this, creating a new pictured link for over color should not be that hard...
If I just would be able to code...