I'm in the process of pulling the half shaft on my daughter's '87 300E and also ran into the tool dilema.
The 30mm axel nut was a piece of cake. Just tapped the axel end with a hammer handle and it was loose.
On the inner sides, one side had the 12mm 12 point internal bolts and the other had E12 (external torx)... go figger?
I found all the tools I needed at my local Autozone. The internal 12 point (aka triple square) set (6,8,10,12mm) was only $12.99. The E12 torx bit was $3.99.
My manual also says that the exhaust needs to be lowered on the driver's side to make room for half shaft removal.
We're heading off to do some mountain biking today. Maybe get a chance to get into it later today.
I'll check back in when I get into it. Not absolutely sure where the noise was coming from, but all indications were the left half shaft.