The set is High Tide.
Do prefer the one with the sentiment or just the birds and sand?
The coasters are either from Home Depot or Lowes - or Amazon. And Amazon also sells the cork backing for the coasters. All you need is the tile, Stazon Ink, Krylon Clear Gloss Coat (it's a spray can) and a cork backing. Super Easy.
I thought these might make nice little gifts. Shall we make some this summer? There is a new set (bundle in fact) that has a nautical theme that would work well for this project. Stay tuned!