zfs grub rescue boot

I had one disk producing read errors in my 15 disk ZFS raid-z2 pool and replaced it offline. Trying to boot the system ended in grub rescue mode: error: no such device: <hex string>. Entering rescue mode... I booted with sysresccd+zfs and was able to import the pool with zpool import -o...

Read lots of threads about grub rescue, but short of mounting a live iso to boot from (can't right now, the remote kvm is half busted), we're stuck at grub rescue> however, looking at (hd0) throught (hd7) (the max # of drives presented to bios by the JBOD controller), I can see...