PC World Aylesbury have a number of document scanners on clearance at £5 each. No manuals/PSU or USB cables - just the bare scanner.
I got the best one I could see (HP Scanjet 4000 series) but there were 4 others there this afternoon (8th August) all at £5 each. A number of colour ptinters too similarly priced but no PSU/ink cartridges - and ink cartridges can be pricy folks. This is probably local but you never know....
And it worked just fine :-)