The other option is to just not use multiple recovery images. An OEM recovery image will contain a lot of stuff specific to that computer model, but you can also use generic Windows recovery images and then store all the drivers, etc. that your different computers need. This would make the recovery less customized to each machine, but would let you get any computer (from the right version of Windows) back to a state of at least basic functionality, and (if you have the drivers and other OEM customizations) you could get it all the way back to the way it came from the factory (though it would take longer).