This is the one I saw also at the Amazon link that I thought was a good alternative if someone wasn't looking to have to fab anything
Amazon.com: JEGS Performance Products 52205 Air Oil Separator: Automotive
The filter would need to be periodically cleaned or changed, but it should do the job well.
Sh0velman, do see a lot of blowby NA? I thought catchcans were more for boosted engines.