Ireland has a record of promoting their breeds (some of us remember the IKC events and a brilliant speech by Sean Delmar on the Kerry in particular) but it hasn’t really been done for quite a few years now. This is going to change in November when the 1st Ireland Heartland heritage Festival will take place. A full catalogue of events has been scheduled and updates will be on here as soon as things are known.
Enthusiasts & Fanciers of Glens 
Can UK Kennel Club registered dogs compete in the Championship Dog Show for Irish Breeds?
I presume they have to be registered with the IKC, could be wrong though.
As we in Ireland have to register our dogs with the KC in order to show in the UK. Championship shows here are held under FCI rules
I wondered whether there might be a “special arrangement” for a one-off show …?
Otherwise, it’s £25.62 (+ extra if you pay by credit card) to register with the IKC, over and above the entry charge (not listed) … for ONE show.