They're a model of the same prototype as the old Hornby ones, but a much newer, finer model.
The Bachmann FGAs have buffer beams at one end, which could also be added at the other and then the body would pass for a CIE 62' wagon. Not quite identical framing etc, but not bad.
The bogies are wrong, but you could do a bogie swap with the IRM 42' flats, which would potentially improve both types! I don't know whether the bogie interface on the models is similar; this might be more difficult than it sounds.
The early Freightliner containers would be good for Ireland in roughly the 1968-1975 period.