Create CreLoaded Shipping Module

Looking for a shipping module that will be based on a pricing matrix and linked to the postcode field of the shipping address. We ship items using palletised delivery when they reach a certain weight and the cost of the delivery depends upon the first two letters of the postcode. We want to be able to input codes and prices eg ST = £45, CW = £40 etc and then link these to automatically provide a pallet delivery cost (dependent on the postcode provided in the customer shipping address) as an option once the weight of the goods reaches a certain level. If the customer is not logged in then we would need to link them to a pricing matrix page giving the full list of postcode prices. We would also like to include an additional option with the pallet delivery (option of a tail lift). This would be a check box at checkout and would increase the value by a set amount. We would be open to any ideas that would improve on the specification above.