check/money order zones and group pricing

Hi

1. At the moment I can only select UK (my home) or everywhere in the world. How can I have 2 separate zones in checks/money orders?

2. I created a new country zone called "distributors only"- that I can manually set a handling fee for in zone postal rates. This is not ideal but we have no way of knowing how much distributor orders will cost to post until we actually go to the post office. We retrospectively place the orders with the true shipping costs and pretend that they will pay by moneyorder- in reality it will be BACS.
   Any better suggestions?

also

3. If I use group pricing as a % can I do away with the above "distributors only" zone and allow manual settings of post charges at the time of ordering?

Thanks in advance and apologises if my ramblings are unclear.