ΔE 26.0, loose: different enough that you should pick on purpose. Amber Green is a little darker, more muted, cooler than Old Gold.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 26). Amber Green is a little darker, more muted, cooler than Old Gold.
The same difference applies the other way round: Old Gold is a little lighter, more saturated, 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 Old Gold on the colour wheel See Amber Green on the colour wheel
All matches: Old Gold equivalents · Amber Green equivalents