Not off hand but you can pick up a metric alan key set at Home Depo for under $10.00.
If you need it attached to an impact (wractchet, etc), cut off a short section (with a cut off wheel) and insert it into a socket, then into the lower end of the fork.. :thumbup:
you might also find you need a damping rod holder to stop it spinning, you can cheaply improvise something though (like shoving a broom handle down there)
(and don't forget to loctite it when you put it back together)
I just did the fork seals and it is either a 6 or 8 mm. Sorry I do not remember for sure. I just used a broom handle to hold the damper rod from spinning. Make sure you replace the gasket on the damper rod bolt when you reassemble, and use loctite as greg said.