Lion has several sources for scanner support. This Apple article lists scanners and printers that they have:
To update the support for those scanners, they have links for driver updates from these vendors HP, Ricoh, Canon,Epson,Brother,Lexmark, Samsung, Fuji/Xerox which if updated after July 20, 2011 for Lion
These other sources have scanners:
Exactscan has several compatible: http://www.exactscan.com/download/compatiblescanner.html
Some HP ones have a trick you can do as documented by this thread:
http://www.hamrick.com/ Vuescan has support for these scanners: http://www.hamrick.com/vuescan/supported-scanners.html
Image Capture support http://macmanus.nl/2013/11/28/use-unsupported-scanner-in-mavericks/ (also lists Lion)
http://www.silverfast.com/show/lion-2/en.html has Lion support for numerous scanners.