How to make drive which doesn't have the MBR bootable?

I suspect my main hard drive is dying, which has Windows 7 on it. So I attached another drive and installed Windows 7 on it, so in case the main drive fails at least I will have a bootable computer. The problem is that the MBR is on the main drive, so without the main drive the new drive fails to boot. How can I make the Windows 7 on the new drive boot without having the main drive connected to my computer? I can't install Windows using a DVD as my DVD writer is busted. Thanks.
Edit: I have a linux live bootable cd, which works with my DVD writer..