When you are purchasing from an oversea sellers, please keep in mind that there are tons of process before the item can reach your local post office. If a local seller delivers an item within 5 days, while the same item from a foreign seller arrive in 7 days, the foreign seller is really doing a good job.

Normally, the foreign post offices take 1-2 days, the airlines take another 1-2 days, the custom inspection also takes 1-2 days. So the normal delivery time should be at least 3-6 days more for a foreign seller. Please give them a good shipping time DSR score if their items take only 3-6 days more than the local ones to arrive.