Other than Worsley Works, there is virtually nothing available in the kit world for the CDRJC now.
Previously, you could buy kits from Backwoods and Parkside Dundas (ex-Ninelines) and get something running.
The peak of Irish NG kit availability (in 4mm NG terms, anyway) seems to have been early 2000s. If you missed the boat, then you really missed it.