I know if you’ve ever had her prescription dispensed at a boots pharmacy before, they can issue and emergency prescription based on the information they have on file. They’ve definitely done this for my mum before with inhalers. Don’t know if it’s different for children. This website suggests other pharmacies do it too.
You can get them over the counter from Tesco/Asda (have done it myself in an emergency). They take your name and GP details so they can let them know you've had another inhaler but it's straightforward otherwise.
Thanks all! I rang 111 and a gp rang back and has faxed a copy to my local boots which opens at 10. She's been wheezy and I was considering a and e hopefully inhaler will stop it otherwise might still be hospital (she was hospitalised a long time ago).