At the moment in the UK it's very difficult to get hold of. I was phoning round pharmacies, they'd say "we don't have stock, I'll check on the computer ... no expected availability from importer for foreseeable future". In the end I found a pharmacy branch of chain where pharmacist trained for travel clinic had left and replacement not yet trained so they still had stock of vaccine because nobody to prescribe it (and I only needed to purchase the stuff for self-dosing). Even then I got their last 2 doses (single box).Ha I was in Melbourne (Australia) travel clinic at the time getting some boosters as I was travelling for more than a year. They had some spare from a batch and offered it for free.
Ian