That projection set is a great find and I'm so glad you rescued it. The cabinet is essentially a big box, so even if you have to build a new one, it won't require tons of fancy cabinetwork.
The same channel selector knob is used in the maker-unknown TV in my Scott 800B Combo:
It's similar to the main tuning knob in the 800B receiver. Cast metal with chrome plating. The small knobs are also identical to those used in the radio.
Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html