Hi,
It looks like it is a pcb mount, momentary type tactile switch i.e. only operated when pressed, doesn't stay in operated position when released. An off - mom tactile switch. Perhaps search online for a pcb mount momentary tactile switch to hopefully find a suitable one.
Without knowing the voltage rating of the switch it may be a guess but unless it is in the AC part of the board usually 24V DC should cover it.
Unsolder the switch and check if there are any manufacturer's markings on it. You can also see the number of leads and mounts it has and their lead spacing etc. The major suppliers for these components, Digikey, Mouser and element14 all have datasheets associated with the components so you can actually check if they're compatible etc.
Way out idea is maybe to take a few pictures of the switch and then do a reverse image search and see what shows up. You never know your luck ;-)
Hopefully a start.
crwdns2934105:0crwdne2934105:0
crwdns2934113:0crwdne2934113:0
crwdns2915270:0crwdne2915270:0
crwdns2889612:0crwdne2889612:0
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