Here is what one search produced:

Handheld Nebulizer/Atomizer - where to get - https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=handheld+atomizer&_sacat=0

From Wikipedia: In medicine, a nebulizer (American English) or nebuliser (British English) is a drug delivery device used to administer medication in the form of a mist inhaled into the lungs. Nebulizers are commonly used for the treatment of asthma, cystic fibrosis, COPD and other respiratory diseases or disorders.