I feel your pain, brother.
The CTS solid-shaft pots should come in at 1/4". Stewart Macdonald provides pretty reliable specs for the stuff they sell, and they offer knurled dome knobs (older telecaster or P-bass style) here:
The traditional Fender Tele knob, also used on many other guitars, basses, lap-steels and other instruments.
www.stewmac.com
and there are, of course, lots of other options out there.
StewMac: Not the best price on the planet by far, but you'll be very likely to get exactly what you see on the webpage.