Sparse, in short supply (5)
I believe the answer is:
scant
I believe this clue is a double definition.
'sparse' is the first definition.
(I've seen this in another clue)
'in short supply' is the second definition.
(I've seen this before)
(Other definitions for scant that I've seen before include "Less than the required amount" , "Minimal (amount)" , "Scarcely sufficient" , "Insufficient, limited" , "Deficient, sparing" .)