I'm with those who say that this is really unrealistic. Yes, there was a Zionist movement since the early 1900s, but it certainly didn't represent the majority opinion among the Jewish people. The Holocaust was a huge trauma, and did result in increased migration to Palestine, but didn't lead to any moves towards state formation - the new population integrated surprisingly well, barring a few minor incidents, and I'm not sure what could have changed that enough to cause the formation of a Republic of Zion, or whatever. In any case, such a state would have to either displace the local Palestinians - utterly unthinkable and unrealistic in the light of the Holocaust - or, more likely, try and assimilate them. This is pretty unrealistic as well.
The only way such a state could survive - and not a very likely chance - would be if some major schism opened up in the Arab world (maybe more states oppose Nasser's plans for a United Arab Republic, rather than essentially just ignoring it until he was deposed), and if this Zion then sided with one faction, eventually becoming a vassal of sorts. Of course, this still doesn't solve the issue of the native Palestinians - they're hardly going to emigrate to Amman or Lebanon, after all, since Palestine is much more productive.