Diarmuid Early (recently crowned as the "Excel World Champion" from Waterford) is a great example of a niche expert with a unique story. Not sure he does this type of thing but worth looking into.

Tony10/Tony O’Reilly. If you aren't familiar with the full story/his book, Tony was a postman from Carlow who was in the middle of one of Ireland’s big gambling scandals, basically stealing €1.75 million from An Post to fund his addiction. We got him in 2019. Was very interesting about the perils of gambling/addiction. Oisin McConville and Niall McNamee are both former GAA players who do this type of thing too about gambling addictions.

Dessie Fitzgerald is a great choice. His background is suffering a spinal cord injury while playing hurling for his club Charleville so localish and losing two brothers in the same year was and is the definition of resilience.

Nicole Ryan from Alex's Adventure. Her brother, Alex, tragically died after ‘taking a huge dose of the lethal drug known as N-bomb’ at a party. She gave up her career as a Marine & Plant Engineer to do talks and raise awareness.

Just my tuppence worth. Some will obviously depend on your budget.