Price Enquiry system

I am currently working on a project where the clients products change price daily.
To help his costumers he wants a price enquiry system where one can select products and send a price enquiry.

I have made this static prototype to clarify: http://jurs.me/enquiry/tab.html

Once the product is selected you press the “Add to enquiry” button the products should be added to the right column.

As you can see there is six categories ( Seafood, pork..etc.) set up as tabs, and sub-categories (Alaskan pollack).

Basicly this is just a large contact form, and i have looked at numerous form plugins. But i havent been able to find one that has the functions i need.

It is important that the client can add more products himself, so user friendlyness is important.

Anyone know of a plugin that may be able to do this? or maby a better solution?