DO NOT CHOOSE DHL as shipping choice they are the ones ripping you off. I have only used them once to ship to the UK and ended paying over half the order price. They are the only shipping company not issuing an invoice with a breakdown of tax and duty they are collecting.
I use the basic airmail and yes it can take several weeks but usually no extra tax is collected.
There is nothing wrong with Iherb company, I have always found them reliable, always shipping the order out the same day i order.