New update. Please note that this is somewhat detailed in order to help those (all three of you, if that, LOL) who might need it in the future or who, like @Rachel, @Redneckerz and a couple of others, have expressed curiosity but may lack some of the technical context. Special thanks to @Blzut3 for the invaluable info that helped me find all this
TL;DR: Now my AlphaServer has aboot 1.0_pre20200212-1 instead of the 0.9b that came with the system.
The Debian sid (unstable or experimental) repository has an updated version of
aboot, the secondary bootloader for Linux on Alpha systems, roughly equivalent to the pre-EFI versions of the Windows Boot Manager (e.g. on Windows XP/7). I used
dpkg-deb to decompile the
.deb package files in "raw" mode, which just extracts them as a directory (kinda like
unzip -d), tar them up,
scp them to the AlphaServer, untar them, repackage them using its (older) version of
dbkg-deb, then install them in the right order using
dpkg -i. Thanks ${DEITY} that while these packages use
.xz tar compression, which nothing in Debian 5 understands and hence the need to decompile/repackage in "raw" mode, they are simple packages that don't use any of the new
dpkg scripting directives (roughly equivalent to those in
.msi or
.nsi files on Windows) that older
dpkg's don't understand.
These commands don't actually install the newer
aboot in the boot sectors; they install a ton of command-line utilities and
man pages (text format manuals, which on Linux are roughly analogous to ye olde WinHlp32 help files), update the raw copies of the bootloader which are located as regular files in the mounted
/boot partition (kinda like an EFI partition for old Linux systems) and leave you to read the man pages to learn how to use the command-line utilities to actually write the relevant one to the actual boot sectors. You have to ignore the 'overlap' warning and override it, as the particular utility for writing on-disk HDD boot files doesn't assume that the raw empty space partition 1 is where the bootloader is meant to go, even though it is its job to put it there

So I had to fire up
gparted (like the Windows disk manager GUI app, but a lot more functional and less fussy) to check things out before doing it, especially as
fdisk gets the partition types wrong (says they are all ext2, but / is ext3). My system even booted correctly after that
Sadly,
sid doesn't have the source code for the new
aboot (it just says 'not found'),
but it is available on GitLab, so I might be able to build it from source myself; let's hope that doesn't become necessary. I haven't tried the new
aboot on a self-built kernel or the one @Bluzt3 mentioned yet; that will have to wait for another 'evening after work' as it's 11pm here in the UK and I will need to get some sleep soon.
But yay, some progress at last
