G'day Obelixxx
Well first up I would check all your universal joints, get under and give them all a good shake around, if one is worn that would be you vibration, if not check your engine and gearbox mounts, with a bar lift them slightly, as they may have seperated between the rubber steel sandwich,also have you checked you wheel bearings lately.
British Off Road will be able to supply parts for you, they are at Forrest Glen near Nambour on the highway
cheers