result.stores, on desktop and mobile, with no flag and at no extra cost. stores is omitted when the SERP has no Stores block. Google shows the block in EU countries.
items holds every merchant of the block, in page order: the 2 that Google shows, then the ones behind “Show more”, with expanded: false.
Text fields are as Google shows them, in the language of the SERP. Some merchants show a price range, a rating or both in place of the description.
Desktop

Stores block in Google Search on desktop
air fryer in Ireland, on desktop, shortened with // …:
Mobile

Stores block in Google Search on mobile
air fryer in Ireland, on mobile, shortened with // …:
Stores structure
Store
position, merchant, link and expanded are always present. Every other field is included only when Google shows it.