Westjet announced last fall that seasonal service to Ireland would start in 2014 (running June through October). Right now there’s a few great deals available from St. John’s at the end of the season.
The best I saw was just $529 total (Oct 19-24). There are a number of other combinations to be found in the $600 range as well. Check westjet.com, Kayak (flex month), or the newly resurrected Google Flight Explorer to find available options.
Service to Dublin is discounted from most other Canadian cities for travel later this year as well, some fares look to be in the $700-800 range.