We have new ones on the shelf buddy. You can order here: http://www.id-workz.co.uk/index.php?main_page=product_info&cPath=3_1118_8_10&products_id=3396&zenid=c2636b2a070b783cfea30bb73be251c7 Cheers Idrees
There's a certain department of the bank you need to ring, they'll send you a form to fill out with all the details of what happened. If they think you're entitled to a refund they will refund you after about a month. Unlikely here though. Robbing cunts! Best bet is trading standards and they'll tell you whether they can help, ring Citizens Advice Bureau first though and they'll tell you what steps to take.
Did you fit them yourself? Did double check all bolts are right? Also check the nut on the top mount as they can work their way loose sometimes. It's the silver one in the middle of the top mount (17 or 19mm socket from memory).
NGK Iridiums, as found here: http://www.id-workz.co.uk/index.php?main_page=product_info&cPath=3_1118_8_1185&products_id=404&zenid=00256d46f6658f31ed41b861e5ad1309
You say you've just bought a new engine, is the headgasket perfectly fine on the engine? If so, I would leave it as it is. If you definitely are changing it, I would personally go for an OEM or 1.2nm Athena.