I would recommend AdMob for the simplest reason that the Google Ad network is so vast, that you'll likely be served with ads. If I'm not mistaken, you can narrow your ads within AdMob to show Israel's ads only.
You can start with AdMob and then you can change it for another one (nothing is written in stone). Naturally, if after AdMob you're planning to change it, is must be one that also serves Israel. Given the healthy startup ecosystem that Israel has, I wouldn't be surprise that there are several mobile advertising companies on the country, you just have to look for them.
Best of luck!