The Nightingale, in Nightingale Lane just up the road from you (!), has one on a Wednesday night http://www.thenightingalebalham.co.uk/whats-on
The Grove, situated between Nightingale Lane and Balham High Road has one on a Sunday night https://www.grovebalham.com/whats-on/
The Devonshire, on Balham High Road, has one on a Tuesday night https://www.devonshirebalham.co.uk/whats-on/
And, no, I don't work for Youngs!!!