One would assume that the standard rims were used, and as noted the base hubcap is likely as no optional rims or caps are called out on the Marti.
For the "exact rims" it is likely they should be the base steel unit, FoMoCo oval logo stamped with "yMm" where y = 7 or 8 (for a 67 or 68 year), M is the makers mark (MotorWheel, I believe) and m = month. That would indicate the correct rim....