Not sure why it needs to be flared though, there is nothing inside the turbo that would require a flare. It is just threads straight down...it doesn't have any points or anything inside.

 

Find a pneumatic supply store.

 

welp, ordered the 1/4 flare from atp...we will see what happens!

 

I'll tell you what happens. It doesn't fit right, you've wasted $15 ordering it, and you should either find a damn pneumatic supply shop to get you the correct fitting or find some other forum's advice to ignore.