Can I redirect the location of savewpar to another location, instead of /tmp/wpardata ?
No, but in this directory are a set of temporary only files about the setup and content of your WPAR. These files are then actually backed up to /dev/rmt0 by default but you can change that to other tapes or to a file in a file system with the -f flag. So /tmp/wpardata is just a useful place to find your WPAR details.