I used to use various mixes of colours, but due to what above poster mentioned about touch-ups, I just went and bought all linen-like colours of the paint line I use (Vallejo model air) to make touch ups easier. As mentioned, the actual shade varied quite a bit so there is no need to get too nerdy about it - I use different shades on different models (and often several on the same model) to get some variation.
The creamy colour on the SPAD 7 is a bit different from the ”natural” linen though.