EBAY: Lilliput 7" touch screen monitor £70 + £6p&p
used lilliput monitor 619GL-70NP/CT about 1 year old.
NOTE: The mouse on the touch screen sometimes moves on it's own to the centre of the screen as though someone touches the centre of the screen. It is still useable but if it does stop working a new touch screen can be brought from http://www.digitalww.com/7TSLilli.htm for $50 plus delivery (about £40 including delivery)
If you do not require a touch screen, the monitor can be used as a standard pc monitor. just don't plug in the usb cable.