To my knowledge in the UK John Gibbs near Bristol was doing some sleeving ,as was Nick Lucca of Watson Bros. Midland Gun services near Shrewsbury bought John Foster's sleeving tooling but I have not heard much about them .
One of the biggest problem with sleeving was sourcing tubes .I know Foster's used to buy their tubes from Italy in large numbers , 200/300 per order . Also with so few guns now being sleeved costs going up that people who have done it in the past find it no longer viable to do so .