If you want a mains one, I'm told these are very good:
http://www.toolbox.co.uk/weller-sp80...LAID=268757820
You'll just need a different tip (a few sizes are available).
If you want a 12v one, the only option is the Spec Racing one (no website, but contact details are here):
http://www.racing-cars.com/page2/scp...p?partno=SP007