How to redownload OS X Lion on a used computer?

I recently bought a used 13-inch Mid 2007 MacBook running Mac OS X Lion 10.7.5.

Processor: 2.16 GHz Intel Core 2 Due

Memory: 2 GB 667 MHz DDR2 SDRAM

Graphics: Intel GMA 950 64 MB

It has had 2 previous owners and did not come with any installation discs. I tried to use the Spotlight search and it kept coming up empty. After trying various command prompts in Terminal and in Single User Mode, I finally went into Disk Utility and tried to verify the disk. I found out that the disk is damaged and needs to be repaired, so I restarted and pressed Command+R because that's what the notification in Disk Utility said to do. It didn't work and the computer booted normally. I researched why this may happen and discovered that the OS X Recovery Partition is missing (I used the command diskutil list in Terminal and it wasn't listed). I have read that the only way to fix this is to reinstall OS X. However, since this is an older machine, OS X is not available for download in the App Store and since I am not the first owner, OS X Lion is not on my Purchases list in the App Store. As I stated earlier, I do not have any of the original installation discs for this computer. Is there any other way I can repair the disk and get the Recovery Partition back? Or did I make a huge mistake buying this used Macbook?