One of the major pains about using a Freesat satellite box, including an expired Sky Box, is that you will not receive any of the Irish channels -- ironically, the ones your TV license is actually paying for. Sky has a deal with RTE to provide Irish channels encrypted on the Sky platform in Ireland only, but for commercial and licensing reasons the unencrypted Saorsat is carried on a different satellite with a smaller footprint, which needs a whole other differently pointed dish.
There are a couple of combo boxes available that gives you a satellite tuner and a Saorview (not Saorsat) tuner which picks up digital terrestrial -- you'll need a separate antenna for Saorview but if you're in a good reception area it could be a cheap indoor aerial. There are some good threads on boards.ie discussing this stuff.
I don't know anything about online options, except that some of them are illegal and will (rightly) incur the ire of the mods if discussed here or on boards.ie.