Can I use a different set of Recovery disks?

My sisters Pavilion p6537c has lost it's hard drive (Windows 7). She doesn't have recovery disks and HP no longer offers them. Can I use my brothers HP (I don't know the model) recovery disks? I understand that the drivers will be different, but can I use them to get a working recovery? I can find the drivers.

Lacking that, I do have a copy of Windows 7, can I do a fresh install and use the windows 7 key that came with the HP?

Thanks for any help,

Den