Maidenstone as Heyward indicates the only death I can find post 1864 is that of Henry Audley who died in 1865 aged 47 suggesting he was born in 1818. As my 'best guess' is that John Audley was born about 1825. This would make Henry 7 years older than John, perhaps they were brothers.
Haywood You say that Henry was the Godparent to Francis Audley baptised in 1850 in Kilteeven again supporting the evidence that Henry Audley could be the brother of John Audley.
Or possibly cousins.
A few Audley mentions in Roscommon newspapers, ignoring those about Lord Audley, the Audley Copper Mine in Cork and the popular novel "Lady Audley's Secret".
Francis Audley, "Roscommon Journal & Western Impartial Reporter", 20th April 1861. He may have been the one with a forge, as the news item is about a pump.
Audley father & son, no first names, "Roscommon Messenger", 31st Dec. 1864.
Bartholomew Audley, Roscommon Assizes; "Roscommon & Leitrim Gazette" 22nd March 1828.
Irish Petty Sessions records are on Find My Past. One of my shopkeeper relatives was fined for using incorrect weights. Farmer relatives were fined for straying animals and not buying dog licences. The Dog Licence Register is also on FindMyPast; I found this useful for locating some people between Griffiths' Valuation and 1901 census, e.g. my shopkeeper's eldest son and a son-in-law of one of my farmers each kept a dog.
U.S. newspapers read by Irish people sometimes carried messages from relatives in Ireland.