That is an awesome ESB. Probably my favorite of all time. I love the slight diacetyl mixed with what I assume is EKG.
You're right about not being able to find a clone; I've looked before. If it were me, I'd start with a solid ESB recipe and tweak it from there. For instance:
95% Maris Otter
5% UK med crystal
Challenger or Target? at boil
EKG 20, 10 and flameout
I'd use WLP005 to try to get some of that slight butteriness that goes so well with ESB's
The only stats I found were from their website:
6.8 % Alcohol by Volume
61 IBU
I'm also interested if anyone else has gotten close to cloning this.