I don't think my husband paid anything for his hearing aides....I think he's classified as having hearing loss from the military but he's also on Tricare so maybe that kicks in some money.
you know my husband did active duty and then joined the Guard...his pension is nothing like regular military but the savings in prescription costs and hearing aides is worth a ton to us...
I would go to the VA. They cover 100% on ones they issue if he is eligible. Can't hurt to ask. Most separation physicals will document hearing test results.
https://www.healthyhearing.com/help/hearing-aids/va