They look smooth... I don't see any residual lathe marks or concentric circles. They also have flathead set screws, are designed for a 6.35mm potentiometer shaft, and seem really precise. I'd gotten some other silver ones I'd used that are a hopeless mess (below):
Top Quality Parts for Guitar Effects Pedals and DIY Music Devices. Knobs, Pots, Switches, Kits, LEDs, Enclosures, Jacks, Wire, Resistors, Capacitors, Semiconductors
stompboxparts.com
Not sure how big your knobs are, but maybe these are similar.
Top Quality Parts for Guitar Effects Pedals and DIY Music Devices. Knobs, Pots, Switches, Kits, LEDs, Enclosures, Jacks, Wire, Resistors, Capacitors, Semiconductors
stompboxparts.com
Not sure how big your knobs are, but maybe these are similar.