You can't, the stick is no longer being made, the same applies with the remote. Getting any new devices that isn't a router from NOW is NOT going to happen.
If your lucky you can source it from eBay.
Otherwise I would ditch the stick and get an Amazon fire stick or full blown Roku stick.
@gavs82008 @Anonymous User
Harvey Norman have the Eire Now TV stick for €9.95:-
I know the Stick won’t work over here in the UK, but if Harvey Norman will ship you one of these, chances are the remote isn’t any different, and at that price, you can just toss the Stick away 😛
@Anonymous User @gavs82008
I’ve been on Harvey Norman’s chat, and they don’t ship to the UK, so you’d have to know someone in Eire who could act as a postbox for you if you wanted one of those 😢
However, I have a new strong possibility, described here:-