I would avoid those suppliers who don't offer a firmware transfer service. When you buy a board from them, you are then stuck with the job of finding someone to adapt it for you. This is because modern HDDs store unique, drive specific information in flash memory. This info needs to be transferred from patient to donor.
Nowadays I only recommend the following suppliers:
http://www.onepcbsolution.com/
http://www.hdd-parts.com/
They will transfer the firmware for free, or for US$10.