I had similar problems finding codes for my 2 tone green car. Morgan paint codes as listed on the car do not seem to mean much.
Eventually I contacted this man at Morgan who sent me suitable translations. Mark.Ledington@morgan-motor.co.uk.
I got the paint in small quantities from these people who were very helpful. helpteam@paintnuts.co.uk
I will try and contact Mark, I did email paintnuts but they couldn’t find any Bentley Velvet Red.