@theharve01 If you're on FB, look up the poultry breeders club of Ireland. They're good for getting you in touch with breeders.
I personally haven't bought or raised any broilers, I don't eat chicken, so the best I can recommend is asking around. If you're in one of the southern counties, try...
We have broilers here, but what you call Cornish we call Indian Game. Some common breeds in the US is hard to find here though and we have a handful of rare breeds that are not known in the US.