The UN, in Resolution 1701, agreed to help pay for damages Lebanon sustained in the recent war, but has not even considered doing so for Israel. You could argue that Lebanon is a non-combatant that got caught in the middle. I think, though, this is a difficult argument to sustain considering that Lebanon created a safe haven and a base of operations for Hezbollah. To me, the more compelling argument is that a UN member nation was attacked by a terrorist organization, and the UN should step in to help out economically. In any event, if you incline to the latter argument, you can sign a petition calling for UN financial aid to Israel.
By the way, I recognize that this is a symbolic exercise only. When one remembers that the UN was busy making available to Hezbollah information about Israeli troop positions, I can’t easily imagine it ponying up money to help Israel recover from Hezbollah’s successful missile strikes.