Does the LEGO Star Wars Holiday X-Wing (4002019) contain any unique pieces?
Checking part inventory for this set on Rebrickable I found following part to be unique:

10169 - Minifigure, Utensil Sack / Bag with Handle in Green

Review posted on New Elementary also suggest pilot's torso and legs are new/unique prints.

The rest seem to be released in other sets. Some parts are quite old or have been produced in small number of sets.