I recommend go out of town, left side of town, head due north. I found a nice little valley with very few roamers and considering the chimaera have quite decent roaming space it was easy enough just to kill one and then pull the next one back to where the first one roamed.

Easy peasy.

Dont let some of the whineheads thats exaggerate here put you off... its not as bad as they make it out to be. I've done this quest before and was the same result back then. 8 in 16 kills or so.