Matchbox paint?

Anybody know of a conversion chart for Matchbox paints? Specifically, I’m looking for 67 “greenish-grey”, for a Polikarpov I-16.

The matchbox ref i assume is a Humbrol color 67 and i can only find one cross ref at hand : Revell = 78 - dark grey
Humbrol list 67 as - matt tank grey. hope this helps a bit !