Finally found these. One user posted a pic with one of these on his geo, but he got the fitting from a coworker and didn't know where the coworker got it from. Alas, I've finally found it
I also found a white one in google that was located at "the find .com" but couldn't find anything else on it. I saved the picture and uploaded it though:
And is this the right size? There's a bunch of different sizes, but was pretty sure it's 1/4 od and 3/8 npt. Correct me if I'm wrong.