Unfortunately since the demise of Firemaster there are few genuine limited life/disposable aerosol extinguishers available - you are stuck with 600g & 800g BC or ABC Powders from Britannia, Jactone or Fireblitz.
Firemaster used to have a nice range of 1 & 2 kg powders and 1 litre foams that were EN3 approved with gauge but aerosol, but these were discontinued after Britannia bought out the assets of the defunct Firemaster.
Most small powders are now 'proper' refillable extinguishers that can be serviced even though some items like ANAF's extinguishers are usually disposed of at 5 years due to the plastic valve, they are refillable and have full parts available if you want.
VOSA's inspection checklist includes a failure if an extinguisher on a vehicle subject to ADR does not have a current service tag.
The only true limited life/disposable extinguishers you would get anywhere near the 2kg capacity are the Kidde Residential 5lb extinguishers sold in the US - Kidde Europe did sell them over here in the late 90's/early 00's but since moved over to using Gloria extinguishers.
Whilst you see some extinguishers on websites as disposable & similar they are actually not.
A pool stock of serviced extinguishers allows a mostly vehicle based extinguisher inventory to be easily changed over if out of date or part used - this is done by some ADR & police fleets