I don't know the answer to your question, but if I had your question I'd call/email and maybe send photos of the jack to Sporty's Pilot Shop. Sort of the Walmart/Dollar store for pilots.
https://www.sportys.com
You might also go to a nearby general aviation airport that has a flight school, maybe a flight instructor could take a look and give you some ideas. Or maybe the Experimental Aircraft Association has a nearby chapter and you could ask for help. Aviators are like Luger collectors, a fraternity and they try to help each other out. By owning the headset you're already a member.