Not too sure about Lahinch, but you'll almost certainly find somewhere in Galway or Ennis to buy it. Nellie is right in saying that we have been particularly sensitive about food imports, particularly since the Foot & Mouth disease scare last year. A number of my friends coming in from UK have had food items confiscated at customs (esp dairy products). I know soymilk is not dairy, but may fall into the same category.