I can't see anywhere on p29 where it mentions leaded EN8?
Basically EN8 comes in three grades; EN8, EN8D and EN8DM. Basic EN8 is what it says it is on the tin. Moving on to EN8D it is slightly harder wearing; the carbon and manganese content is limited to upper end of the ranges specified for EN8. There is a free machining version, EN8DM, but it contains a bit more sulphur (about 0.2%) and a little more manganese. Lead doesn't come into it.
I have stock of all three variants, but haven't done any comparative machining trials.
Andrew