I've seen the weird key symbols before, on teleprinters/teletypes. Here is a British Telecom teleprinter with nearly the exact colour scheme (thought slightly different layout):
LEDs are embedded in many of the keycaps with wires that plug into the switch.
The main block of keys are mostly 1B3B switches. The non-LED "Auto Dial" key is a 1B3C switch - slightly firmer.
Shift keys are 1B3A switches, which are slightly lighter than 1B3B. The Return key is a 1B1B, with a 3A1D switch to stabilize. (felt on top)
The "Run" key is a 9B3C. Strangely, the "Just" key, which has no LED, uses a 9B3B LED switch and LED-style keycap. (spot to fit LED, but no window)
The feel of this keyboard is fairly smooth linear, but not "the best". My Victor 9000 Keytronic foam & foil and some vintage "T" ALPS are smoother.