I can't say what tapes and DVDs are available in Ireland, GD. But, the extra scenes are available here in the US on the DVD set, and in a compilation called "The Godfather Saga" that's shown on TV regularly. It's GF and II in chronological order, spliced together.
Amazon.com has sites outside the US. Can you check your local Amazon to see if they sell the DVD set? That's the most reliable place to get the extra stuff.