Clementines are for sale. Singular in Italian is clementina. Plural is clementine. In other words the final a changes to e. This is how most words that are feminine (that take la as the article) become plural. You also have to change the article la to le.
They cost 3.5 euros per kilo. Note how in Italian the comma is used 3,5 euro. Euro is technically a made up word. The plural is the same: un euro and dieci euro. In English we add an s: one euro, ten euros.
The clementines come from (provenienza) Spain (Spagna). They look good.