The Specifically Selected Goods and Services Tax Act Article 10

The taxable value for an imported specifically selected good shall be the sum of the customs taxable value and import tariff.If the specifically selected good of the preceding paragraph is subject to commodity tax or business tax, the taxable value shall be the sum of the amount calculated pursuant to the preceding paragraph plus the commodity tax and business tax.
中文原文 特種貨物及勞務稅條例第10條
進口特種貨物之完稅價格,應按關稅完稅價格加計進口稅後之數額計算之。
前項特種貨物如係應徵貨物稅或營業稅之貨物,應按前項數額加計貨物稅額及營業稅額後計算之。

English translation for reference only; the Chinese text prevails. Not legal advice.