I have to imagine that was Teddy from Onebadhawk. He has been carrying airfoil buttons for a while now.
When I use rail buttons, I have pretty much exclusively shifted to airfoils. I especially like the Unistrut airfoils - they are beefier than the round ones and hold up a 100+ rocket nicely.
Apogee does have them.
Personally, I like the ones from SCP:
https://scpconcepts.com/rocketry/airfoil-rail-guides/
Scott at SCP has made the Unistrut ones in the past and I believe Kenny from Performance Hobbies had some of the SCP Unistruts on hand last time I talked to him.
Teddy's airfoils are interesting because they are a two piece design:
http://onebadhawk.com/onebadhawk-airfoiled-rail-guides.html
I have seen others around, but those are vendors I trust and I have used their airfoils.