I had my three carbs completely refurbished by Carburetter exchange based at 28f high street leighton buzzard Beds LU7 1EA Tel 01525 371369
https://www.carburetterexchange.co.uk or
sales@carburetterexchange.co.uk
They are very helpful and knowledgeable - for info my complete rebuild including the dreaded VAT and postage (within UK) about gbp 285.
The job took about 6 weeks and the results are perfect.
Regards
Mike Say