No reason a cask can't be transported from the UK and be in perfect condition when it arrives. What happens between when it gets here and when it gets to the customers glass is much more important.
Cask beer requires a skill from the publican that keg beer does not. Does the pub have a cellar set up to deal with casks and will there be someone there who understands about stillage time, soft and hard spiles, etc?
Having said that, I would rather see an Irish micro brewing the beer and it might even end up cheaper than shipping from the UK and arranging for a bonded warehouse. You should enquire at least.