Yes, the Weincell zinc-air batteries. These don't last as long as the old mercury batteries or alkaline batteries, but they are the correct voltage, and they have the correct discharge pattern for older meters. In the U.S., the cheapest place to get them is B&H. Not sure about the UK, but Calumet would be a good possibility.
A friend of mine had to get a new battery for her F1. But instead of going thru all the aforementioned hassle, she just took it into the local camera repair shop and they recalibarated it to accept the new batteries. Very cheap and ulimately easier.