This gives:
# apt install linux-image-5.17.0-1-librem5
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following NEW packages will be installed:
linux-image-5.17.0-1-librem5
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 14.9 MB of archives.
After this operation, 78.4 MB of additional disk space will be used.
Err:1 https://repo.pureos.net/pureos byzantium/main arm64 linux-image-5.17.0-1-librem5 arm64 5.17.0pureos1
404 Not Found [IP: 138.201.228.45 443]
E: Failed to fetch https://repo.pureos.net/pureos/pool/main/l/linux-next-librem5/linux-image-5.17.0-1-librem5_5.17.0pureos1_arm64.deb 404 Not Found [IP: 138.201.228.45 443]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?