I suppose you could try constructing your own connecting flight with El Al via TLV if it someone did end up being cheaper. However, I read a report in one of the forums about someone from Cyprus (I believe...) who caught an UP flight from Larnaca to TLV in order to connect to an El Al long-haul flight. He reported that despite the signage at TLV for transfer passengers, they didn't actually have provisions for it and made him go through passport control.