Girl's bike needed

Jackolas Just a light girl's bike (not fixed) for my girlfriend, who is 5'8'' (Old peugeot or raleigh or whatever). Budget £100 plus or minus depending on the blah, blah. Anyone got one? Know a good second hand bike shop? I honestly can't stomach buying something from Brick Lane market. Apologies for the absolutely non-fixed nature of this post, though I am pumping money back into the impoverished fixed wheel community.... Thanks.

i have a bike girls bike you can have free, it is large but with a 5'8'' girl it might work.
the frame is a lugged raleigh 'wisp', 700c wheels, 5speed block on the back, single chainring up front.