OK, but in this case the discussion about reviving superblocks is moot: you can't revive a superblock on a FS located on some disk cannot see. The question is not: "how can i repair the superblock",...
man zfs
tells to use the zfs send command for data backup and zfs receive for a restore.
The output can be redirected to a (big!) file or a device (e.g. a tape drive that is represented as a...