I carelessly broke the screen on my asus 32gb nexus 7. I bought a 16gb nexus 7 as a replacement 9simply lacking funds to get another 32gb) and I am wondering if there is a way to swap their hard drives?
There is no "hard drive" as such in these. Instead there's a Kingston flash module. You'd need a steady hand and knowledge of desoldering BGA's in order to swap it.
You can't swap the "hard drive", since it is flash memory chips soldered to the circuit board, but you should be able to swap the screens over. It should be easy enough to work out how to do it, so long as you have a suitable screwdriver to take it apart, but you may want to check out the teardown at ifixit.com.