Thanks for the recipe, believe me I've looked in every local supermarket and small stores I could find there are no unsweetened products other than soy.
I did find hemp milk and oat milk but none of it was unsweetened, same goes with coconut milk, almond milk is scarce in the UK.

I have also looked on many websites and I still can't find anything, I can only find these products on US websites :/

Also Isn't a zucchini the same thing as a courgette?