ΔE 13.8, fair: the same colour family, but not a straight swap. RLM 65 Light Blue is noticeably darker, cooler than Marine Mist.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). RLM 65 Light Blue is noticeably darker, cooler than Marine Mist.
The same difference applies the other way round: Marine Mist is noticeably lighter, warmer.
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 Marine Mist on the colour wheel See RLM 65 Light Blue on the colour wheel
All matches: Marine Mist equivalents · RLM 65 Light Blue equivalents