DC IN connector
Manufacturer: Phoenix Contact
Manufacturer PN: 1827868
https://www.phoenixcontact.com/en-pc/products/printed-circuit-board-connector-mc-15-2-gf-381-1827868
Mating connector
Manufacturer: Phoenix Contact
Manufacturer PN: 1827703
https://www.phoenixcontact.com/en-us/products/pcb-plug-mc-15-2-stf-381-1827703
More info
Remote power button connector
Manufacturer: Molex
Manufacturer PN: 353630460
Remote power button pinout
More info
SolidRun remote power button cable:
SolidRun PN: SRBD-CABBTN
Description: 1m cable with panel mount power button (black) with integrated blue LED (IP67 rating)
Panel mount power button: https://www.e-switch.com/product-catalog/rp8100-series-round-illuminated-pushbutton-switch