Making the shipping work like this with two different costs for each item would require a bit of customizing with eCart is not something that would be supported within PowerStore. Since you have eCart you could make the updates that would be needed but there are a few steps to this.
The first thing you would need to do is add the shipping costs columns to your items table. Next you would need to update the admin insert and update pages to allow you to set and edit the values. Once you have got the back end stuff worked out you can begin on the front end.
For the front end the first thing to do would be to update the cart files to make it so you can edit the cart without it breaking other parts. Here is a link to the tread with the updated files:
showthread.php?t=12820
You would need to add in the two new columns to the cart. You would then need to set the bindings for the new columns in the add to cart server behavior. This would get you a setup with the shipping charges set for each item in the cart. You would then need to set a session variable during the checkout to determine what zone they are in. You would then setup two charge rules, one for zone 1 and one for zone 2, then based on the zone in the session variable you would trigger one charge over the other. For the amount of the charge you would just base it on the subtotal for the zone 1 or zone 2 column depending on which zone rule you are working with.