Similarly to transportation expenses which are included within the cost price of a stock item, so are the import and other taxes you won’t be able to get back from the state and / or tax authorities. As IAS 2 puts it: “The costs of purchase price of inventories comprise the purchase price, import duties and other taxes (other than those subsequently recoverable by the entity from the taxing authorities).” 

For an example you buy items from a country you’re asked to pay import taxes on the purchase. Say you’re buying 100 items of something with a unit price of 50 and the import taxes are in total 200. By using simple mathematics we can calculate the unit price. The total amount you’ll pay for the items is 700 (calculation is as follows: 100 items multiplied with 50 that’s the unit price and adding 200 that’s the import tax). Now, as you bought 100 items, the price per unit you paid is thus 7 (calculation is as follows: 700 in total as the amount paid / payable divided by total units that’s 100). On your balance sheet you show that you got inventory (debit entry) and the amount is thus shown as 700.

When selling those items, you expense them by the unit price that include the import tax since it’s already accounted within the unit’s cost price in the detailed stock ledger.