Can be found here, if anyone needs one at a good price:
http://www.justoffbase.co.uk/54mm-1-Sq-Drive-Socket-Single-Hex-Pattern-AK261-06-Sealey
that is cheap they are usually about £50 ish
Thats where I brought mine from.
I emailed them over a year ago when they didnt have them. Thought I may as well try and see if a silly price came up! They said they would get them in - £12 at the time so price has got better! :wiggle