Have you tried Mouser Electronics? Their website is mouser.com. They sell a large variety of Davies knobs, and there’s no minimum order on stocked items. An electronics manufacturer that I used to work for orders a lot of parts from Mouser, and I’ve even ordered parts from them, as an individual, for home use. They’re a good company. They have a lot of stuff, though, which can make it hard to find what you want, but I suggest going to their website, click on “Electromechanical”, and then on “Knobs & Dials”. This will bring up over 1,000 different knobs, but there is a “Select Manufacturer” option. Just choose “Davies Molding” and click on the “Select” button. That will reduce the search to strictly Davies knobs. There are a few pictures; a lot of knobs don’t have a picture on the list, but they have a link to the catalog page, which has a drawing of all the knobs. Or, you could find the knob that you want on the Davies site and look for the part number on the Mouser site.