Halon 1301 can still be purchased, in the form of an existing extinguisher, however, you cannot get an extinguisher refilled. At the Newhaven boat fair, there was a stall with 50-60 extinguishers for £10 each. I suspect he does other fairs aswel.
The recodnised replacement is FM200, does a similar job, but more expensive. personally i will stick with my Halon 1301s until Dec 2003, which is the deadline for this type.
The interesting bit is... how do you get rid of Halon?. surprisingly, I read in a trade mag, that it is burned, baffled me too.
Now how did I guess that once they'd outlawed it the replacement would be more expensive...? Not as if THAT happens whenever something is outlawed now is it!
Having just been through this exercise, here's what I found...
Once the Halon (BCF) extinguishers are out of date, your insurance is invalidated, so get 'em changed. You cannot buy replacement Halon (unless they're old stock), and in any event, it will be an offence to be in posession of Halon from sometime in 2003.
The alternatives are: CO2 (very bulky, needs plumbing in, expensive), Dry Powder (cheap, but messy, gets ingested by the engines), and Halon replacements (expensive - I was quoted £200-300 for what I believe was something like the Pyrogen system).
The only practical solution I found was Dry Powder, but on advice, I contacted my insurers, and got written confirmation that they were happy for me to fit auto dry powder extinguishers to the engine bay. The reason for this is that the powder will be ingested by the engine in the event of a fire with the engines running. The powder should knock the fire down (what else is it there for?), but the engines may well be totalled, as podwer mixed with oil/diesel will form a very nice grinding paste... Apparently, some insurers have been known to be awkward about the collateral engine damage, and have tried to only pay out on the direct fire damage.
My existing extinguishers were Firemaster ones, and they were very helpful - 0208 852 8585, ask for Tim Bartlett - and do an exchange service at preferential prices. 2Kg dry powder replaces a 1.36Kg Halon, and costs £23.76, for instance.
With thanks to Tim at Firemaster, a very knowledgeable bloke in the chandlers on Barrack Road, Christchurch, and Euromarine Insurance...