I was wondering where I could order the o ring for the oil seperator because that is leaking, and what would need to be replaced on the front end of my car with 379,000 km on it.

 

I'm assuming the oil separator is what everyone refers to as the "black box" that is on the back of the engine. The factory catch can. O-ring for that is most likely a dealer only if it hasn't been discontinued. As for the front end, if you've never done anything to it you're likely due for upper and lower ball joints and tie rod ends. Jack the car up and give the wheels and up and down and side to side shake to check. Crawl under and make sure your power steering rack isn't leaking. Check that your axle boots aren't cracked or leaking.