John Armour seems to be the man you're looking for on WikiTree, although he seems to have had a son John too.
I added some information that is behind a paywall, but you should be able to find out more at the NB Archives website, where you will find indexes to land records and any birth, marriage or death records that were registered. You may be aware that these records weren't mandatory until close to 1900, so the newspaper clippings indexed on this site are an important resource. The 1851, 1861 and 1871 Census records give interesting details, like immigration dates, occupaitons, and so forth. Like the newspaper, spelling or surnames was sometimes unpredictable, so I would leave myself open for various versions of the surname when searching.
There was another Armour family, David Armour came from Scotland, so you may want to take care not to confuse your Irish John with David's much-younger Scottish son John (who was born in NB in 1838).
Don't hesitate to send me a private message if you need help with any of these sources.