The Internode Mirror contains a wide selection of software for download by Internode customers.
File Download Mirror Directory Listing
Index of /pub/debian/dists/bullseye/main/installer-arm64/20210731+deb11u12/images/netboot/debian-installer/arm64/grub/
Index of /pub/debian/dists/bullseye/main/installer-arm64/20210731+deb11u12/images/netboot/debian-installer/arm64/grub/