ΔE 16.6, loose: different enough that you should pick on purpose. Rusty Metal is a little lighter, much more muted than Viking Gold.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Rusty Metal is a little lighter, much more muted than Viking Gold.
The same difference applies the other way round: Viking Gold is a little darker, much 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 Viking Gold on the colour wheel See Rusty Metal on the colour wheel
All matches: Viking Gold equivalents · Rusty Metal equivalents