While I had my car up on a lift today I noticed the pillow ball mount on the driver side rear toe arm had some grease on the outside of the rubber boot. (right under the rotor where it mounts to the knuckle, good amount of seepage/leak but not completely exploded)

I do plan on replacing this ASAP, but was planning on doing my first auto x in a week and a half.

My question is: is it safe to run the car this way for 1 autocross event if I can't replace the part in time?
and: Should I replace with aftermarket kit? If so which one?

(I have not noticed any difference in the way the car drives)
If it matters, I'm currently running Tein springs, but am switching to KW V2 this week.

 

Probably gonna be fine. You can check the play in the ball joint by putting big slip joint pliers on it through its axis and pressing. So basically put the jaws on the top of the ball joint and the other jaw on the threaded stud. If its more than a 1/8 inch or so its pribably risking a break. I doubt seriously its that sprayed though.