Bulleid wagons, GSR opens, any old vans from GSWR to modern CIE ones…and of course flat wagons if your making a car trains (some of which were GNR in origin ) and yes after hearing that I had a massive facepalm having past your GNR flats at raheeny and not purchased em
what you need in terms of loco stock for west cork running (well bantry anyway) is
bandon tank
at lest 2 C class locos
An AEC railcar
GSWR F6, J10 and the other 4-4-2 loco with the box ivatt cab
the CBSC tank from 00 works (aka J24)
Of course I’d you apply some imagination as I would, you could add
An A class (went there at least once )
a 121
maybe one or two Black and Tan things (some coaches were painted Black and Tan in Rocksavage works)
WLWR 4-4-2s if you can make one
A midland J26
an E401 class (trialed on the courtmac line)
Molaga, argideen no.90 and 100 (no idea why they would be there)
A Baldwin (lol)