To install an earlier version, you'd do as you do at the moment i.e. dig
   out your old sources from your backups, and install from that.  This is
   current-users, though, and my older (patched) version of top stopped
   working around about the time that the swap changes were incorprated.
   The conspiracy theorists amongst us are invited to contribute reasons
   why this might have happened.

the old version stopped working because the method of finding out swap
space resources was moved from being "grovel the kernel structures" to
"ask the kernel for info", as the old structures no longer exist..