Help! Does anyone know of an artist called Mario Hurtado
and The Royal Marimba Orchestra. (Imperial-LP 9012) I
heard this band at the San Franscisco World's Fair in 1937
and would like to find their recordings. EF

Since it's two years after your post, you're probably not checking
the site any longer, but at the xylotopia website we have
lots of old recordings of marimba bands.
We have lots of Hurtado Brothers!
Best Regards,
Steven