I'm slowly finding my sources ... yes, my design, my circuits, my assembly/soldering, my laser cut panels with back lighting ... that I want to sell to the public.
I was able to find the some parts elsewhere with the same level of quality for about 1/3rd the price wholesale. FYI -- $9 was just for the knob, that does NOT include to rotary encoder and/or switch. So $16.60 for just one rotary encoder/switch ... add 6 of these, laser cut panels, backlighting, circuits, dimmers, various other switches and buttons etc. ...
To be honest, I didn't really expect anyone to provide "sources" but thought I'd give it a shot. Sources are a closely guarded commodity for those building to sell.
Cheers, Rob.