I also use [broken link removed] Look at - DCB Group and (also based in Ireland). I've bought external drives, replacement hard disks, scanners, misc. computer cards, memory, etc, both for business and home use. It's always worthwhile to check prices elsewhere before purchasing.
I found the exactly same type of hard drive as my broken one - a 5 year old Toshiba MK6021GAS from this site. http://www.memorysuppliers.com/
It's also a good one supplying tons of computer parts.