We will be arriving in Tel Aviv (Ben Gurion) in late October. Is it possible to buy a cheap GSM cellphone in Tel Aviv, along with a SIM card that would give me an Israeli phone number? I'm looking for a Pay-As-You-Go phone that I can use during my 3-week vacation. Hopefully it would also be unlocked, so that I could use it elsewhere in the world by simply buying the appropriate SIM card. Thanks!