H3C SFP-GE-10-SM1310-BIDI совместимый 1000BASE-BX модуль SFP WDM (BiDi) 1310nm-TX/1550nm-RX 10km DOM

Ordering was easy and the product arrived really quickly however no mention was made of the import/duty tax that needed to be paid to the carrier before I could take possession of the goods.
I realised that there might be duty to be paid but had no idea how much until DHL emailed me. Although I got a print-out of this amount it wasn't in invoice form so not sure how to put it through my accounting system?
Is it possible for FS.com to inform us of the tax before we purchase the goods please.