Debian 12: need nvidia-settings to join 2 2560x1440 into a 2880x2560

[Roger Price]

In Debian 11 I have two 2560x1440 displays side by side in portrait mode.  With 
the package nvidia-settings I created an xorg.conf which set these two displays 
to work as a single 2880x2560 display, Very nice.  I would now like to do the 
same thing in Debian 12, but with Debian 12 I cannot find the package 
nvidia-settings.  The page https://packages.debian.org/bookworm/nvidia-settings 
talks about the package but doesn't mention a repository that I can access with 
synaptic.

Is there some way of getting to this package?
Roger