Getting Spray Can Colour Matched in London

[fly fisher]

Hi,
Can anyone know somewhere in preferably West London where you can get a spray can mixed to a colour.

Preferably somewhere which can scan the paint and match to that.. A spectrometer I think

Having difficulty getting a colour match on my morgan.. its meant to be connaught green but the factory colour code does not match after nearly 20 years of use..

Thanks,
Will