I have the same scanner, and after installing 24.04 from scratch on a new ssd, I also had the same problem. I got it working after finding this:
which tells you (In addition to installing libsane1) to install a version of libsane from a different ubuntu release:
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It appears that in 2017, someone decided to rename libsane to libsane1. Currently, libsane is just used for backwards compatibility purposes. It has no files itself. It does nothing else but depend on libsane1. However, the libsane package is not available in Ubuntu 23.10 and there is high probability, we wouldn't see it it future releases.
For your driver to work, first you will have to install the libsane1 package. And the workaround for libsane is to download and install the package from another Ubuntu release. In the example below, I am using libsane from Ubuntu 23.04 (Lunar Lobster) for amd64 architecture and it works. You can download and install it with:
sudo apt install libsane1
wget http://mirrors.kernel.org/ubuntu/pool/universe/s/sane-backends/libsane_1.2.1-1_amd64.deb
sudo dpkg -i libsane_1.2.1-1_amd64.deb
I was able to run the sudo ./install.sh after that.
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