Having finished the nappies and extra cloths (and washed them), I did have a go at some wool soaker covers. Not having a baby to practise on, I'm not sure whether the sizing will be close enough. I used
Rita's Rump Cover pattern as a starting point and tried to insert ribbing from the cuffs, collar and waistband to act as the elastic for the back and leg holes. I'm not sure whether I got enough stretch in to be reasonably effective. Anyway, they cost nothing, didn't take long to make and used a couple of scrap jumpers I'd been hanging onto for too long....