Hello
I think the townland is Munny not money in Ballyboy Co Offaly
Kilcormac is in Offaly (or Kings County). There is a web page Kilcormac.com which might be helpful.
When looking up Kilcormac for that time you would have to look up Frankford.
There is one O'Brien family in the town of Kilcormac still (check out eircomphonebook and put in o'brien and kilcormac and residential)
The Griffiths Valuations of Irealand was done between 1848 and 1864 - for Ballyboy there are no O'Brien but 3 Brien
Brien Catherine Ford Mountrath Street Ballyboy Offaly
Brien John Ford Fairgreen Street Ballyboy Offaly
Brien John Ford Freagh Ballyboy Offaly
In the Titheapplotment books in 1826 there is a Michael Brien, Munny, Ballyboy, Kings County
Offaly is referred to as Kings County and Kilcormac is referred to as Frankford. Other regional names, locations and bounderies may have changed so it is often worthwhile researching all the available locations.
Hope this might be of some help
Geraldine Smith