Hmmm... looking at the Farnell list there is only one that is in stock and suitable - and unfortunately their minimum order is £20:

Order Code: 8371245
Manufacturer: FRIWO
Manufacturer Part Number: 22.0360.
Description: ADAPTOR, AC/AC 9V 1.9A; Voltage, output:9V ac; Current, output max:1900mA; Voltage, input:230V ac;
Price: £11.00