This original painting is listed in  Pether's catalogue simply as "Andes" - but is clearly a cover illustration for an romantic adventure novel, possible with Andes in the title - likely created c. late 80s to early 90s.  Soon as I am able to source it, I'll list the official title  . . .  Until then, my pricing takes that search into account! Well done in gouache and acrylic on illustration board, 15.75" x 10" and comes with a label affixed to the back attesting to authenticity.