you can have a veg boullion if l remember right not regular stock cubes too salty l think now l could be wrong , so maybe you should wait for another reply
Cambridge do a savoury drink - ask your CWPC about it.
Alternatively, a few people use Marigold Bouillon (the lower salt variety) as a substitute. If I remember rightly, you can have up to a level teaspoon of it per day.