In Reply to: I booked through their website last week posted by Best price on Tuesday, 14. January 2014 at 19:55 Bali Time:
They should only require the CC number and expiry date or in addition the name on the card.
The CSC number should not be required and I would never scan, fax or verbally give it away.
Only ever use the CSC on a website set up to accept it.