‘I worked in Northern Ireland as a teenager. Can I buy extra UK pension years?’

Q I’ve been reading about how people living in Ireland who worked in the UK for at least three years can become eligible for a UK state pension by buying additional UK national insurance years. I’m from Northern Ireland originally and worked part-time jobs in the North from the ages of 16 to 20. I came south at the age of 21 and have only ever worked here, on a professional basis, ever since.

Would I have any eligibility to the UK state pension and would it make sense for me to purchase the top-ups?.