I checked the Auto Color Library for the 1933 Graham Pearl Essence Lacquer. See their statement below ("Pearl Essence Lacquer - impractical to match"). How would a show car be judged that originally wore a pearl essence color if it is impossible to match the original color? Would the car be marked down if it used mica in the paint instead of fish scales?
I did a brief survey of known 1933 Grahams on a registry put together by a Graham Club member. While not all the data is complete, (and 1 or 2 cars seem to appear every year) my survey shows that of the 34 eight cylinder cars, 7 are known to have been painted in pearl essence. Of the 31 6 cylinder cars, at least 3 were painted in pearl essence (most of the paint codes are not known for the 6 cylinder cars).
According to the 1932 article posted above from Industrial Finishing, the process of painting pearl essence color seems rather straight forward. Two double coats of the ground color (same color as used for tinting the pearl essence), let the color coats dry, three coats of the pearl essence, let it dry and lightly sand with 400 paper, and then a mist coat of high grade thinner.
While I am no expert at painting, it seems that if you could come up with a formula for the ground color that you could experiment with ground fish scales to make a pearl essence paint. Fish scales appear to be available from oversea sources. Any thoughts or would it be impossible to do?