Restore the OSX to a MacBook Air 2008 original without recovery partition

Hi,

I received a macbook air original 2008. After fix the fan which was full of dust and noise, I started it and all was OK. So, I decided to erase the old files and make a format to make a new clean instalation.

After reboot, I tried to restore the OSX via internet acording the option on the recovery menu. But they asked me for and ID for Apple used to buy mountain lion. I have a macbook pro 15 new so I used my apple ID and doesnt work. So after that I made a recovery partition on a portable hard disc and I made a boot disk with Maverick. I start pressing Option aot choose the portable hard disc to boot. But a prohibited sign color grey appears. If I treid to boot without the portable hard disk a blinking folder appears which indicates tha mac cant find the boot files on the mard disc. SO i connect the portable hardisk on the USB of the MAC pressing Option key. The Wi FI bar and the disk appears. But I can not boot it. I understand than even with a broken hard disk inside, I can boot at least from an external harddisk.

I have to mantioned that for a reason I dont know the reovery partition inside the mac was erased

it is possilbe than maverick is imcompatible with macbook air intel 2008?

it seems that came with mountain leopard as original OSX but I can not find ir even in internet. I dowloaded from Apple the recovery disk assitance and I made one with my macbook with maverick intalled but again the prohibited sign appears.

I hope some one can help me, best regards.