ΔE 6.5, close: similar, with a visible difference side by side. UK Light Stone is a little darker, more muted than Light Mustard Khaki.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). UK Light Stone is a little darker, more muted than Light Mustard Khaki.
The same difference applies the other way round: Light Mustard Khaki is a little lighter, more saturated.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Light Mustard Khaki on the colour wheel See UK Light Stone on the colour wheel
All matches: Light Mustard Khaki equivalents · UK Light Stone equivalents