Saint Lucia is about 510 times smaller than New Mexico.

New Mexico is approximately 314,310 sq km, while Saint Lucia is approximately 616 sq km, making Saint Lucia 0.2% the size of New Mexico. Meanwhile, the population of New Mexico is ~2.1 million people (1.9 million fewer people live in Saint Lucia).
Tip: This to-scale comparison of New Mexico vs. Saint Lucia uses the Mercator projection, which distorts the size of regions near the poles.