Don, If you check with the local paint stores, many of the manufacturers have put together a large selection of color chips, in one booklet, for use as a custom paint resource.

For example Sherwin Williams calls theirs "Muestrario De Color", and R-M calls theirs "Rod & Custom Colors". I know PPG also has one, and I will assume most of the major producers have followed suit.

This gives you an easy way to compare various available shades of pearl and opaque colors.