That was what i had in mindif i ahad got it. I suppose that it have been near enough the last of them. The post office ran them in the orange and white for a while after that http://www.rte.ie/archives/2017/0315/859886-retired-postman-retains-van/. The phone part of the company went blue and white didnt they? The post office went green all over in which year i couldn't say.
Do you have more pictures of it? I would love to see some pictures of it as it is a sight that one would hardly ever see these days on the Irish roads
and when you think about it there were thousands of them around 20 years ago. I was talking with a postman friend that used to drive them back in the day
and he said it was many the day that he had to run after it down the road as when he got out to deliver the post the handbrake would slip off on its own and the van would roll away and end up in a dyke more often than not on the narrow country roads.