I also have an old Mustek scanner with outdated drivers, with no hardware issues. Luckily, my scanner is USB, and VMware Workstation allows to forward complete USB devices to a guest OS. When I need to scan something, I fire up a virtual machine with 32-bits Windows XP inside, with OG drivers, and scanning software.
Does Vuescan support it?
Aunt's computer had been upgraded to Windows 10 and HP printer/scanner had the scanner part stop working...
I was cursing Microsoft and HP for half an hour reading various failed workarounds. I was getting serious "shaving the yak" vibes until I found Vuescan.
Best $25 purchase for a software in the last 10 years.