ostler vs sais

ostler

noun
  • A person employed at an inn, hostelry, or stable to look after horses; a groom 

sais

noun
  • A groom, or servant with responsibility for the horses. 

verb
  • Used to represent a nonstandard pronunciation of says. 

How often have the words ostler and sais occurred in a corpus of books? (source: Google Ngram Viewer )