Since such a solution was not readily available, we are building a custom solution that integrates WooCommerce and e-conomic for one of our clients. Also we have planned a solution to integrate WooCommerce and Vend POS System but have not started working on it yet.
We would be happy to build this solution for whoever is interested.
We do custom solutions and could definitely work out a solution for you regarding this. We have planned out a similar solution.
You can checkout the below link for more details http://wisdmlabs.com/blog/create-custom-product-builder-product-designer-wordpress/