At that age there’s a good chance the headphones work off infrared technology rather than Bluetooth. So if you look on Amazon it might be difficult to find ones that work. I’d try looking on eBay for something…maybe search for any info you can find on the unit to get a match. I will say when we had bunk dvd players like that in a 2007 Itasca mh some old infrared headphones from a minivan worked, so you might have luck finding something used from an automobile that’ll work. Good luck.
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