ΔE 8.6, close: similar, with a visible difference side by side. Stormvermin Fur is a little lighter, more saturated than RLM 81 Version 3.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Stormvermin Fur is a little lighter, more saturated than RLM 81 Version 3.
The same difference applies the other way round: RLM 81 Version 3 is a little darker, more muted.
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 RLM 81 Version 3 on the colour wheel See Stormvermin Fur on the colour wheel
All matches: RLM 81 Version 3 equivalents · Stormvermin Fur equivalents