I looked into it, but between this that an tother it's a hard one to solve. I looked at metal as opposed to glass from a safety and longivity point of view, the minimum purchase would give all craft drinkers in Ireland a couple each.
And from a legal point of view they cannot be filled after 10pm any day, not that I would expect most pubs to go with that mind you.
Price of take away draught beer was something that some publicans said they wouldn't budge on, which boggles the mind really.
From talking to brewers and customers, the result is that buying your own growler (online) is the only option, as it doesn't benefit publicans or brewers to supply them as they can be used in other pubs, or for some one else's product.
But I'm gonna keep on this until I'm told it's not going to happen.