These are called out as an 8mm pushbutton switch, primarily used in HMI interfaces for automated manufacturing and CNC machine tool control panels.
Brands: ITW-Licon, Omron A3D series, EAO 19 series, NKK HB series and a relatively new Asian maker, but their MOQ is 1000-3000pc min per part# unless you can find a Alibaba seller who will do piece pricing, (expect the switch "manufacturer name" to be different for each seller of course).
Most manufacturers supply these switches in 8, 12 & 16mm (round mounting hole diameter, not the switch cap size), round, square and rectangular button shape with momentary or maintained contacts. EAO also offered push-on connectors (wired and PC mount)
NOTE: Each vendors mechanical and electrical pinout arrangement varies so they are often NOT directly mechanical or electrical compatible.
EAO has the widest range of contact options, but only provide 2 switch contacts in SPST config with at least four contact configs to choose from, where ITW, NKK and the Asian mfg offer a standard SPDT on 3 pins.
All leds are standard T-1 type with slip-in contacts, so you can replace them easily, but will need to provide an external ballast resistor for appropriate brightness. The Asian mfg leds are a proprietary molded slip-in led cassette that contain internal resistors for specific voltages (6, 12, 24v...) and are AC/DC compatible (internal bridge). If you design these into your gear, make sure to spec an easy to find led/switch format for future maintenance (a few spec sheets attached).
I replaced about 2400 switches on the BOP Focusrite console and a great many on various vintage ISA rackmount channels. They have a limited lifespan due to their extremely thin plastic bodies and age much faster if they are in gear with elevated internal temperatures or are used often.
If you have to service a vintage ISA module with these switches, be VERY careful around their panel/controls wiring. After about 5 years the controls-to-PCB jumper wires often become stiff & brittle, and any movement while replacing another switch or pot can easily fracture several nearby switch bodies at the metal ferrules that secure them to the front panel. Heavily used switches will often break at the dress ring, just under the pushbutton cap. In heavy use expect to replace these switches every 6-10 years, (United Recording,s Focusrite is now being re-switched for the fourth time since its install in the early 90's).
Except for the Asian mfg and EAO, all others have discontinued this switch type over the last 20 years or so and yes,... EAO pricing is very painful. Also note that with EAO, you often have to order the switch body, led and button cap as separate items.
You might find a few of the more affordable NKK left in vendor stock as they only discontinued them about two years ago, but cap/led colors and contact types may be very limited. I think I bought the last 200 from Mouser and Digikey in 2022, but I am sure more can be located with enough digging.
Additional data: Not all ISA range gear uses these switches. The late model ISA front panel segment pictured earlier in this thread may actually be a CIT LPH series or E-switch WBL series (as Scott2000 pointed out) illuminated PC mount pushbutton.
